Answer:
[tex]\boxed {\tt x=5}[/tex]
Step-by-step explanation:
We want to solve for [tex]x[/tex], therefore we must isolate it on one side of the equation. The equation is:
[tex]3x+5=20[/tex]
5 is being added to 3x. The inverse of addition is subtraction. Subtract 5 from both sides of the equation.
[tex]3x+5-5=20-5[/tex]
[tex]3x=20-5[/tex]
[tex]3x=15[/tex]
x is being multiplied by 3. The inverse of multiplication is division. Divide both sides of the equation by 3.
[tex]\frac{3x}{3}=\frac{15}{3}[/tex]
[tex]x=\frac{15}{3}[/tex]
[tex]x=5[/tex]
Let's check our solution. Plug 5 in for x and solve.
[tex]3x+5=20[/tex]
[tex]3(5)+5=20[/tex]
[tex]15+5=20[/tex]
[tex]20=20[/tex]
This checks out, so we know our solution is correct.
The solution to 3x+5=20 is x=5.
