Answer:
x = 4 / 3, y = 7 / 3
Step-by-step explanation:
We are given the following system of equations;
{ 7x - y = 7, ⇒ Let us multiply the first equation by 2,
x + 2y = 6 }
2 * ( 7x - y = 7 ) ⇒ 14x - 2y = 14 ⇒ Now add the two equations
+ x + 2y = 6 + x + 2y = 6
14x + x = 14 + 6 ⇒ Simplify
15x = 20,
x = 4 / 3 ⇒ Now substitute this value of x into the first equation to solve for the value of y,
7 * ( 4 / 3 ) - y = 7 ⇒ Simplify,
28 / 3 - y = 7,
y = 7 / 3
Solution; x = 4 / 3, y = 7 / 3
A scientist has two solutions, which she has labeled Solution A and Solution B. Each contains salt. She knows that Solution A is 35% salt and Solution B is 80%
salt. She wants to obtain 90 ounces of a mixture that is 40% salt. How many ounces of each solution should she use?
Solution A:
Solution B:
Answer:
80? bc yhu cant use solution a because it only has 35...i think
Step-by-step explanation:
if im wrong sorry
The requried scientist should use 80 ounces of Solution A (35% salt) and 10 ounces of Solution B (80% salt) to obtain a 90-ounce mixture that is 40% salt.
Let's assume the scientist uses x ounces of Solution A and y ounces of Solution B to obtain the desired mixture.
From the information given, we can set up the following equations:
Equation 1: The total amount of solution is 90 ounces, x + y = 90
Equation 2: The amount of salt in the mixture can be expressed as, 0.35x + 0.80y = 0.40 * 90
Simplifying Equation 2:
0.35x + 0.80y = 36
To solve these equations, we can use substitution or elimination. Let's use the substitution method.
From Equation 1, we can express x = 90 - y and substitute it into Equation 2:
0.35(90 - y) + 0.80y = 36
31.5 - 0.35y + 0.80y = 360
45y = 4.5y = 10
Substituting y = 10 back into Equation 1:
x + 10 = 90
x = 80
Therefore, the scientist should use 80 ounces of Solution A (35% salt) and 10 ounces of Solution B (80% salt) to obtain a 90-ounce mixture that is 40% salt.
Learn more about equations here:
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Maya is researching energy costs. She made a table of the cost for different numbers of gallons of gasoline. How much will 12 gallon cost?
A.$7.80
B.$23.40
C. $31.20
D. not enough information
Answer:
The answer is B
Step-by-step explanation:
BEcause I took the test
Answer:
B. $23.40
Step-by-step explanation:
1. You have to divided the cost by the number of gallons to get the the cost per gallon
2. multiply the number of gallons by the cost per gallon that you found
Then you have your answer!
Which ordered pair is a solution of the equation?
2x + 4y = 6x - y
a. only 4,5
b. only 5,4
c. both 4,5 and 5,4
d. neither
pls answer
ill mark brainliest
Answer:
b. only 5,4
Step-by-step explanation:
alejandro rosario or mattia polibio?
Answer:
Alejandro Rosario
Step-by-step explanation:
he is just really cute, well both of them are, but his personality seems nice.
Answer:
ale
Step-by-step explanation:
(1/3)^3 Evaluate the expression. This question is designed to test your intelligence.
Answer:
1/27
Step-by-step explanation:
That means
1/3 * 1/3 * 1/3
1/9 * 1/3
1/27
Answer:
1/27
Step-by-step explanation:
(1/3)^3
1/3*1/3*1/3
1/27
4) If z/3 = 6, what is z equal to?
Answer:
z/3 = 6
multiply both sides by 3
z/3 * 3 = 6*3
z = 18
find the volume, help please all numbers are in inches, will mark brainleist
Prism volume will be base area times height. We have a right triangular base, so its area is half the product of its legs, area (1/2)(6)(8)=24. The prism has a height 13. Multiplying we get a volume of 24×13 = 312 cubic inches.
Answer: 312 cubic inches
Solve for x.
-30 = 5(x+1)
Answer:
−30=5(x+1)
Step 1: Simplify both sides of the equation.
−30=5(x+1)
−30=(5)(x)+(5)(1)(Distribute)
−30=5x+5
Step 2: Flip the equation.
5x+5=−30
Step 3: Subtract 5 from both sides.
5x+5−5=−30−5
5x=−35
Step 4: Divide both sides by 5.
5x5=−355
x=−7
Answer:
x=−7
Answer:
x = -7
Step-by-step explanation:
Since this problem has the distributive property, we can simplify the problem.
-30 = 5x + 5
Now we have to subtract 5 from both sides because of the +5.
-35 = 5x
To find the answer, we have to move all the real numbers to one side, the variable on the other. To do this, we can simply divide both sides by 5.
-7 = x
x = -7
What is the product?
2x(x-4)
O 2x2-4
O 2x2-8
O 2x2 - 4x
O 2x2-8x
Answer:
d. 2x^2-8x
Step-by-step explanation:
ure just doing distributive property.
The product of 2x(x-4) is 2x² - 8x
HOW TO OPEN BRACKET?In a mathematics, algebraic expressions can be in bracket. This bracket means we multiply all the variables outside by those inside.
According to this question, we are given the following expression: 2x(x-4)
This means that 2x multiples x and -4 independently.
That is; 2x × x and 2x × -4
2x² - 8x
Therefore, the product of 2x(x-4) is 2x² - 8x.
Learn more about factorization at: https://brainly.com/question/6810544
In quadrilateral PQRS, PQ = QR = RS = SP, PR = 14, and QS = 48. Find the perimeter of PQRS.
Answer:
100 units
Step-by-step explanation:
Lengths of diagonals:
PR = 14
QS = 48
Since all 4 sides are equal in length, it's a rhombus
Length of each side:
sqrt[(14/2)² + (48/2)²]
sqrt(625)
25
Perimeter = 4 × 25
= 100
The side length of the rhombus is 25 units. Then the perimeter of the rhombus PQRS will be 100 units.
What is the perimeter of the shape?The complete stretch of a shape's border is referred to as the perimeter in geometry. A shape's periphery is calculated by summing the lengths of all of its sides and borders. Its dimensions are expressed in linear units like centimeters, meters, inches, and feet.
In quadrilateral PQRS, PQ = QR = RS = SP, PR = 14, and QS = 48. The diagonal of the rhombus intersect at a right angle. Then the side length of the rhombus is given as,
a² = (14 / 2)² + (48 / 2)²
a² = 49 + 576
a² = 625
a = 25
Then the perimeter of PQRS will be given as,
P = 4a
P = 4 x 25
P = 100 units
The side length of the rhombus is 25 units. Then the perimeter of the rhombus PQRS will be 100 units.
More about the perimeter of the shape link is given below.
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WILL MARK THE BRAINLIEST!!!!!
[only answer the 2nd and the 3rd]
Answer:
2. 120 cm^2
3. 3,750 cm^2
Step-by-step explanation:
To find the surface area of a rectangular prism, find the surface area of each side, then add them together.
2. There are two different shapes of faces on this prism (as with all rectangular prisms). One face's surface area has a measure of 4 cm by 6m. To find the surface area of that face, multiply each side length. 4 * 6 = 24. Let's call this length A.
Then, find the surface area of the other face. The other face has a measurement of 4 cm by 3 cm. 4 * 3 = 12. Let's call this length B.
Now, find the amount of each face on the prism. Length A appears 4 times: the front, back, top, and bottom are all the same shape. Length B appears 2 times: the left and right sides. Therefore, multiply length A's surface area by 4 and length B's surface area by 2.
24 * 4 = 96
12 * 2 = 24
Lastly, add both numbers together.
96 + 24 = 120
Adding the label, we get the final answer: 120 cm^2.
3. Now, apply the same steps to problem #3.
One face has a measurement of 45 cm by 25 cm. This means that the surface area of that face is 1,125 cm. Let's call this length A.
The other face has a measurement of 15 by 25. This means that the surface are of that face is 375 cm. Let's call this length B.
Length B appears 4 times, and length A appears twice. Evaluating 375 * 4, we get 1,500. Evaluating 1,125 by 2, we get 2,250.
Lastly, adding 2,250 to 1,500 and adding the label, we get the final answer: 3,750 cm^2.
Help please
0.3 [. ] 0.4
What is the decimal
<,> or =
what are the dimensions of a square with a perimeter of 48 inches
Answer:
Each side is 12 inches long. The area is 144 square inches.
Answer:
12 by 12 inches
Step-by-step explanation:
12 times 4 (congruent) sides =48
A box contains 7 yellow, 5 blue, and 4 red balls. Three balls are drawn at random. Find the probability that:
Exactly two balls are yellow
Answer:
1/6 is the probability. im pretty sure
Please please please please please please thank please please please help me please ASAP
Answer:
4
Step-by-step explanation:
3x^2 + 2(y-1)/x+y^2
3(4)^2 + 2(3-1)/4+3^2
3x16+2x2/4+9
48+4/13
52/13
4
PLEASE HELP ON THIS QUESTION! I WILL MARK YOU BRAINLIEST IF CORRECT :) TYY
Answer:
no it's not a reflection
Step-by-step explanation:
a reflection would not be upside down like that, it would be the same thing rotated
Emma can run 4.5 miles in 36 minutes. How many miles can she run in 2 hours if she keeps a constant pace?
Answer:
13.34
Step-by-step explanation:
Answer:
15 miles is the answer, I hope this helps
Step-by-step explanation:
1. Set up a proportion
2. Convert 2 hours to 120 minutes
3. Cross multiply then divide the remaining number in the proportion
Mr. Massy started baking cupcakes at 7:15 a.m. The cupcakes finished baking at 7:40 a.m. How long did it take the cupcakes to bake?
Answer:
25 minutes
Step-by-step explanation:
If the cupcakes started baking at 7:15, then it takes 25 minutes to get to 7:40.
Answer:
he took 25 min
Step-by-step explanation:
40-15 =25
help so hard!!! i need help
Answer:
1. b
2. are like terms
Step-by-step explanation:
1. this is b because when you distribute, each of the terms in the parentheses will get multiplied by 3.
2. these are like terms because they have no variables. they are just numbers so they are like terms
The lowest point of elevation in the United States is at Death Valley National Park in California at 282 feet below sea level. The Dead Sea in Israel is 1,360 feet below sea level. Write a division expression that could be used to find how many times greater the Dead Sea lies below sea level than Death Valley. Then determine how many times greater. Round to the nearest whole number.
Answer:437
Step-by-step explanation:I took the test
The chart below shows the distribution of weeds in a yard.
A circle graph titled Lawn weeds. The largest proportion is crab grass, then dandelion, then clover, then chickweed.
A lawn-care specialist chooses a random sample from the yard and determines the number of weeds in the sample. The results of the sample are shown in the table below.
Weed Type
Number
Dandelion
2
Clover
3
Crab Grass
2
Chickweed
2
Which explains whether or not this is a representative sample?
Yes, this is a representative sample because each type of weed is represented in the sample.
Yes, this is a representative sample because each type of weed is represented approximately the same number of times in the sample.
No, this is not a representative sample because each type of weed should be represented in proportion to the number of weeds actually present in the yard.
No, this is not a representative sample because each type of weed should be represented exactly the same number of times in the sample.
Answer:
Its c,No, this is not a representative sample because each type of weed should be represented in proportion to the number of weeds actually present in the yard.
Step-by-step explanation:
Answer:
c
Step-by-step explanation:
Suppose that y varies inversely with x. Given x=-3 when y=-105. Find y when x=15
Answer:
21
Step-by-step explanation:
It is given that y varies inversely with x.
[tex]y\propto \dfrac{1}{x}[/tex]
[tex]y=\dfrac{k}{x}[/tex] ...(i)
where, k is constant of proportionality.
It is given that x=-3 when y=-105. Substitute these values in equation (i), to find the value of k.
[tex]-105=\dfrac{k}{-3}[/tex]
[tex]-105\times (-3)=k[/tex]
[tex]315=k[/tex]
Now,
[tex]y=\dfrac{315}{x}[/tex]
Substitute x=15 in the above equation.
[tex]y=\dfrac{315}{15}[/tex]
[tex]y=21[/tex]
Therefore, the value of y is 21 when x=15.
Combine the Expression:(10x - 4) + (-7 + x)
Answer:
11x-11
Step-by-step explanation:
(10x-4)+(-7+x)
10x-4-7+x
11x-11
Answer:
11x-11
Step-by-step explanation:
10x+x=11x
-4+(-7)=-11
11x-11
if this is right a brainliest would be very appreciated!
A concert hall sells tickets in three different price ranges. For each price range, there are both adult and child
rates.
Concert Hall Prices
Adult Child
Rates.
Which statement describes the relationship between the adult ticket prices (a), in dollars, and the child ticket
prices (c), in dollars?
It cost Leah $1.50 to send 10 text messages. How many text messages did she send if she spent $7.05?
PLEASE ANSWER
Answer:
47 text messages
Step-by-step explanation:
7.05 divided by 1.50 which is 4.7
The multiply 4.7 times 10 which give you 47.
10 texts = $1.50
/10 /10
1 text = $0.15
# of texts = $7.05/$0.15 = 47 texts
Answer:
47 texts
The diameter of a circle is 8 cm. Which equation can be used to find its circumference? WILL MARK BRAINLIEST
A. C =π×88
B. C=π × 4
C. C = 16×π
D. C=π × 8
Answer:
The equation is D. C= π × 8.
Step-by-step explanation:
Solve the equation in the image
Answer: 55
Step-by-step explanation:
[tex]\sqrt[3]{4x-4}=6[/tex]
Begin by cubing each side of the equation to get rid of the cubic root.
[tex](\sqrt[3]{4x-4})^3=(6)^3\\ 4x-4=216[/tex]
add 4
[tex]4x-4+4=216+4\\4x=220[/tex]
Divide by 4
[tex]\frac{4x}{4}=\frac{220}{4}[/tex]
[tex]x=55[/tex]
Answer:
it is zero
Step-by-step explanation:
there are 12 inches in 1 foot
write an equation to find the number of inches in any number of feet
Answer:
divide the number of inches by 12
Step-by-step explanation:
Will Give Brainliest
Which function can be used to model the graphed geometric sequence?
f(x + 1) = Five-sixthsf(x)
f(x + 1) = Six-fifthsf(x)
f(x + 1) = Five-sixths Superscript f (x)
f(x + 1) = Six-Fifths Superscript f (x)
Answer:
f(x + 1) = Five-sixths Superscript f(x)
Step-by-step explanation:
Answer:
The answer is A. f(x + 1) = Five-sixthsf(x)
Step-by-step explanation:
-4x -4y=-5
12x + 12y =15
What do the following equation represent
Answer:
x=5/4 -y
Step-by-step explanation:
12x-12x 12x-12x 12 divided by 0 = undefined
subtract 12 from both sides of the equation then divide by 12.
so the answer would be:
y= 5/4 -x
