Question

Simplify the expression using the laws of exponents. 36x−2y2 15z−3 A) 12x1/2y2 5z3/2 B) 12x2z3 5y2 C) 12y1/2x2z3 5 D) 12y2z3 5x2

Answer 1

`\frac{12 {z}^( 3) {y}^(2) }{5 {x}^( 2) }`

Explanation:

We want to simplify:

`\frac{36 {x}^( - 2) {y}^(2) }{15 {z}^( - 3) }`

The trick is that when a negative index in the numerator comes to the denominator , it becomes positive.

The vice-versa is also true.

That is:

`{a}^( - n) = \frac{1}{ {a}^( n) }`

and

`{a}^(n) = \frac{1}{ {a}^( - n) }`

We simplify to get:

`\frac{12 {z}^( 3) {y}^(2) }{5 {x}^( 2) }`

The last choice is correct.