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Solve in picture. Mathematics problem.

Solve in picture. Mathematics problem.-example-1

1 Answer

4 votes
Cross Multiplication!

(4)/(7) =
(x-3)/(21)
4 × 21 = 7 × (x-3)
Distribute 7 into the parenthesis:
84 = 7x - 21
Take 21 to the other side:
84 + 21 = 7x
105 = 7x
Divide by 7 on both sides:

(105)/(7) =
(7x)/(7)
( 7 and 7 cancels out )
15 = x
x = 15
User Marcello DeSales
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