How do you solve x equals 2x squared-36?

Answer 1

38

Answer 2

Make it a straightforward quadratic equation: 2x^2 - x - 36 = 0

Factorise: (2x - 9)(x + 4) = 0

If the whole expression equals 0, one of the bracketed terms must equal 0,

so x = 9/2 or -4

Check: 2 x 81/4 - 9/2 - 36 = 40½ - 4½ - 36. This equals 0;

2 x 16 -(-4) - 36 = 32 + 4 - 36. This also eqauls 0.

Given solution is therefore correct for both values of x.