Let's solve for y.
4x+7y=28
Add -4x to both sides.
4x+7y+−4x=28+−4x
7y=−4x+28
Divide both sides by 7.
7y/7=−4x+28/7
y=−4/7x+4
32 students choose a favorite topping for their slices.
Let x be the total number of students.
1/2 of the total students, or 1/2x, choose pepperoni.
1/4 of the total students, or 1/4x, choose extra cheese.
1/8 of the total students, or 1/8x, choose sausage.
4 students choose mushrooms.
We know that together, these equal the total number of students, x:
1/2x+1/4x+1/8x+4=x
We will use 8 as the common denominator:
4/8x+2/8x+1/8x+4=x
Combining like terms:
7/8x+4=x
Subtract 7/8x from both sides:
7/8x+4-7/8x=x-7/8x
4=1x-7/8x
4=1/8x
Divide both sides by 1/8:
4÷(1/8) = 1/8x÷(1/8)
4/1÷(1/8) = x
4/1×8/1 = x
32/1 = x
32 = x
Answer:
81
Step-by-step explanation:
9 x 9 = 81
So, 81 is the perfect square.