Question

When asked his age , Michael said ‘ if you square my age , then subtract 12 times my age , the result is 85. how old is he

Answer 1

17yrs Old

Explanation:

By the given statement,

Factorize if possible or use general solution for quadratic equation.

x2 - 17x + 5x - 85=0

x • (x-17)+ 5 • (x-17)=0

(x + 5) • (x - 17) = 0

Therefore,

(x + 5)=0 or (x - 17)=0

x=-5 or x=17

Discard the negative value

x=17 is considered.

Hence, Michael is 17yrs old