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Please help me answer this

Please help me answer this-example-1

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Hello from MrBillDoesMath!

Answer:

b = 25

h = 7

Discussion:

Given: A = bh = 175

From the diagram: b = 4x+1 and h = x + 1. Substituting these in the formula for Area gives

(4x +1) (x+1 ) = 175 =>

(4x + 1 )* x + (4x + 1)*1 = 175 =>

(4x^2 + x) +(4x + 1) = 175 =>

4x^2 + 5x + 1 - 175 = 0 =>

4x^2 + 5x - 174 = 0

Via the rational root theorem ( roots are of form p/q where p is a factor of 174 ( +\-2, +\-3, +\-29 and q is a factor of 4 (+\-2) ) we find that x = 6.

Hence b = 4x + 1 = 4(6) + 1 = 25 and h = x+1 = 6+1 = 7

Regards,

MrB

P.S. I'll be on vacation from Friday, Dec 22 to Jan 2, 2019. Have a Great New Year!


User Shahin Ghasemi
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