Question

if 7 is added to twice a number and this sum is multiplied by 4 the result is the same as if the number is multiplied by 5 and 10 is added to the product. what is the number?

Answer 1

-6

Explanation:

Lets assume a number be "x".

As given, lets put in an expression:

=
`4* (2x+7)` --- (first)

=
`5x+10`----- (second)

As known both the expression are same.

⇒
`4* (2x+7)` =
`5x+10`

Opening the parenthesis and distributing the number 4 with 2x and 7.

⇒
`8x+28= 5x+10`

subtracting both side by 28 and 5x

⇒
`3x= -18`

cross multiplying

∴ x=
`(-18)/(3) = -6`

x= -6

On subtituting the value of x on the expression.

`4* (2x+7)` =
`5x+10`

We get, -20=-20, which is equal.