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3 years ago

Area of triangle=42, the width is x+3 and the length is 2x+8, find the value of x

Mathematics

1 answer:

beks73 [17]3 years ago

8 0

Step-by-step explanation:

Area of triangle = 1/2 × the width × the length

42 = 1/2(x+3)(2x+8)

42 = 1/2×2×(x+3)(x+4)

42 = (x+3)(x+4)

(x+3)(x+4) = 42

x² + 7x + 12 = 42

x² + 7x + 12 - 42 = 0

x² + 7x - 30 = 0

(x-3)(x+10) = 0

x = 3, -10

x can't be -10 because the width and the length should be only + values

x = 3

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