Question

What substitution should be used to rewrite 6(x + 5)2 + 5(x + 5) – 4 = 0 as a quadratic equation?

Answer 1

Answer:

Step-by-step explanation:

put x+5=t

6t²+5t-4=0

solve for t and then find x

6t²+8t-3t-4=0

2t(3t+4)-1(3t+4)=0

(3t+4)(2t-1)=0

t=-4/3,1/2

x+5=-4/3

x=-4/3-5=-19/3

or x+5=1/2

x=1/2-5=-9/2

Answer 2

(6 + 5)(x +5) - 4 = 0