Question

√217-x = x-7 solve for x

Answer 1

Answer:

The solution to the given equation is x = 21 or x = -8

Step-by-step explanation:

Given,

√(217-x) = x - 7

squaring both side we get,

217 - x = (x - 7)²

=> 217 - x = x² - 14x + 49

=> x² - 13x - 168 = 0

splitting the middle term we get,

=> x² +8x - 21x -168 = 0

=> x(x+8) - 21(x+8) = 0

=> (x-21)(x+8) = 0

=> (x-21) = 0 or (x+8) = 0

=> x = 21 or x = -8

Hence the solution to the given equation is x = 21 or x = -8

I hope it helps.

Answer 2

Answer:

Step-by-step explanation:

√217-x = x-7

Sq. both sides

217-x = x² + 49 -14x

x² +49 -217 -14x +x = 0

x² -13x -168 = 0

x² -(21-8)x - 168 = 0

x(x-21) + 8(x-21)=0

x=21,-8