Answer:
12.
a.
i. (x-9)(x-3)
ii. x = 9 or 3
b. (y+10(y-10)
Explanation:
12.
a.
i.
Two numbers that multiply to make 27 and add to make -12 are: -9 and -3.
Put into brackets so you have: (x-9)(x-3)
ii.
Consider each bracket as its own equation.
x-9=0
x=9
x-3=0
x=3
b.
Difference of two squares