Pls explain How do do all of these and say answers
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Answer:
QUESTION ONE-
Cross multiply:
5 * 15 = 12 * y
Simplifying
5 * 15 = 12 * y
Multiply 5 * 15
75 = 12 * y
Solving
75 = 12y
Solving for variable 'y'.
Move all terms containing y to the left, all other terms to the right.
Add '-12y' to each side of the equation.
75 + -12y = 12y + -12y
Combine like terms: 12y + -12y = 0
75 + -12y = 0
Add '-75' to each side of the equation.
75 + -75 + -12y = 0 + -75
Combine like terms: 75 + -75 = 0
0 + -12y = 0 + -75
-12y = 0 + -75
Combine like terms: 0 + -75 = -75
-12y = -75
Divide each side by '-12'.
y = 6.25
Simplifying
y = 6.25
QUESTION TWO-
Cross multiply:
8 * w = 20 * 6
Simplifying
8 * w = 20 * 6
Multiply 20 * 6
8w = 120
Solving
8w = 120
Solving for variable 'w'.
Move all terms containing w to the left, all other terms to the right.
Divide each side by '8'.
w = 15
Simplifying
w = 15
QUESTION 3-
Cross multiply:
s + 1 * 8 = 4 * 4
Simplifying
s + 1 * 8 = 4 * 4
Reorder the terms:
1 + s * 8 = 4 * 4
Reorder the terms for easier multiplication:
8 * 1 + s = 4 * 4
1 * 8 + s * 8 = 4 * 4
8 + 8s = 4 * 4
Multiply 4 * 4
8 + 8s = 16
Solving
8 + 8s = 16
Solving for variable 's'.
Move all terms containing s to the left, all other terms to the right.
Add '-8' to each side of the equation.
8 + -8 + 8s = 16 + -8
Combine like terms: 8 + -8 = 0
0 + 8s = 16 + -8
8s = 16 + -8
Combine like terms: 16 + -8 = 8
8s = 8
Divide each side by '8'.
s = 1
Simplifying
s = 1
Step-by-step explanation:
on the 1st one you are looking for the percent.First you have to multiply 15 times 5 and =75.Then divide 75 divided by 12 and = 6.25% and your y=6.25
the second one you are looking for w.You multiply 6 times 20=120.Then divide 120 divided by 8 and =15
And the last one I don't know but you simplify and the answer is s=1