Question

The average of 35, 45 and x is equal to 5 more than twice of x. What is the value of x?

Answer 1

Answer:

13

Step-by-step explanation:

35+45+x/3=2x+5

35+45+x=3(2x+5)

80+x=6x+15

80-15=6x-x

65=5x

x=65/5

x=13

Answer 2

Answer:

$\huge\boxed{x=13}$

Step-by-step explanation:

The average of 35, 45 and x:

$\dfrac{35+45+x}{3}$

5 more than twice of x:

$2x+5$

The equation:

$\dfrac{35+45+x}{3}=2x+5\\\\\dfrac{80+x}{3}=2x+5\qquad|\text{multiply both sides by 3}\\\\3\!\!\!\!\diagup\cdot\dfrac{80+x}{3\!\!\!\!\diagup}=3(2x+5)\qquad|\text{use the distributive property}\ a(b+c)=ab+ac\\\\80+x=(3)(2x)+(3)(5)\\\\80+x=6x+15\qquad|\text{subtract 80 and}\ 6x\ \text{from both sides}\\\\80-80+x-6x=6x-6x+15-80\\\\-5x=-65\qquad|\text{divide both sides by (-5)}\\\\\dfrac{-5x}{-5}=\dfrac{-65}{-5}\\\\\boxed{x=13}$