Apr 02
Topic : Solve for x
Problem : Solve (x+2)/(x-3) = 42/(x+7)
Solution :
Cross multiply,
(x + 2) (x + 7) = 42 (x – 3)
x + 2x + 7x + 14 = 42x -126
x + 9x + 14 = 42x – 126
– 9x – 14 = -9x – 14(adding -9x and -14 on both sides)
x = 33x – 140
x – 33x + 140 = 0
x – 28x - 5x + 140 = 0
x(x – 28) - 5(x + 28) = 0
(x-28)(x-5) = 0
x-28 = 0 or x-5=0
x = 28 or x = 5
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