Question

How to use substitution to solve

Answer 1

Given:

A. Evaluate
`(3)/(8)x-4.5` when x=0.04.

B. Evaluate
`8.4n-3.2p` when n=2 and p=4.

To find:

The values of the given expression at the given values.

Solution:

A.

We have,

`(3)/(8)x-4.5`

Putting x=0.04 in the above expression, we get

`(3)/(8)(0.04)-4.5`

`=0.015-4.5`

`=-4.485`

Therefore, the value of the expression at x=0.04 is -4.485.

B.

We have,

`8.4n-3.2p`

Putting n=2 and p=4 in the above expression, we get

`8.4(2)-3.2(4)`

`=16.8-12.8`

`=4`

Therefore, the value of the expression at n=2 and p=4 is 4.