Question

Raul simplified the expression, as shown below. –[3h + 7h(2 – h)] = –[10h(2 – h)] = –[20h – h] = –19h Describe the error(s) in Raul’s work.

Answer 1

He should have  worked out 7h(2 - h) first before adding the 3h. (first step)

2nd step he multiplied the 2 by -10h  but he also should have multiplied the -h by the -10h ( Distributive law)

Answer 2

Raul should have first removed the innermost grouping symbols, the parentheses, by distributing 7h.

He should not have added like terms before multiplying.

Raul only multiplied the 10h times the 2 and forgot to multiply it through the quantity to the –h.