Question

Simplify the expressions and find the value if x = -4.
a) 19 - 5/4 x^2 - ( -9 + 8/3 x^2)​

Answer 1

Step-by-step explanation:

$19 - \frac{5}{4} {x}^{2} - ( - 9 + \frac{8}{3} {x}^{2} ) \\ 19 - \frac{5}{4} ( { - 4}^{2} )+ 9 - \frac{8}{3} ( { - 4}^{2} ) \\ 19 - \frac{5}{4} (16) + 9 - \frac{8}{3} (16) \\ 19 - 20 + 9 - ( \frac{128}{3} ) \\ - 1 + 9 - ( \frac{128}{3} ) \\ 8 - ( \frac{128}{3} ) \\ - \frac{104}{3}$