Question

The product of Minas age in year 5 years ago and har age 8 years later is 30. Find her present age

Answer 1

Answer:

Let the present age is x years

5 years ago age is x-5

age after 8 years is x+8

product of these two is thirty

so

(x-5)(x+8) =30

x²+3x-40-30=0

x²+3x-70=0

x²+10x-7x-70=0

x(x+10) -7(x+10) =0

(x-7) (x+10) =0

so x=7 or -10

we need positive number

so Minas present age is 7 years