Question

The value of the expression StartFraction 2 x squared Over x EndFraction plus x (100 minus 15 x) when x = 5 is
119.
129.
135.
145.

Answer 1

GIVEN :

The  expression  is Start Fraction 2 x squared Over x End Fraction plus x (100 minus 15 x)

TO FIND :

The value of the given expression when x=5

SOLUTION :

Given that  the expression  is Start Fraction 2 x squared Over x End Fraction plus x (100 minus 15 x)

The given expression can be written as:

$\frac{2x^2}{x}+x(100-15x)$

To find the value of the given expression when x=5:

That is put x=5 in the expression $\frac{2x^2}{x}+x(100-15x)$

$\frac{2x^2}{x}+x(100-15x)$

$=\frac{2(5)^2}{5}+5(100-15(5))$

$=\frac{2(25)}{5}+5(100-75)$

$=2(5)+5(25)$

$=10+125$

$=135$

∴ $\frac{2x^2}{x}+x(100-15x)$ when x=5 is 135

∴ the value of the given expression $\frac{2x^2}{x}+x(100-15x)$ when x=5 is 135.

Option C) 135 is correct.