Respuesta :
Answer:
D. x = 1.2.
Step-by-step explanation:
5x^2-36x+36=0
Use the 'ac' method:
ac = first coefficient * the last
= 5 * 36 = 180.
We need 2 numbers whose product is 180 and whose sum = the coefficient of x (that is -36).
These are -6 and -30, so we write -36x as -30x - 6x:-
5x^2 - 30x - 6x + 36 = 0
5x(x - 6) - 6(x - 6) = 0 Now factor by grouping ( x - 6 is common), we have:
(5x - 6)(x - 6) = 0
So the solutions are 6/5 = 1.2 and 6.
