Solve the equation 7x=15+6 using substitution.
To solve this equation using substitution, we will solve for one variable in terms of the other in one of the equations, and then substitute that expression into the other equation.
Let's start with 7x = 15 + 6.
We want to solve this equation for x, so we need to isolate x on one side of the equation.
First, we can simplify the right-hand side of the equation by combining 15 and 6:
7x = 21
Next, we divide both sides of the equation by 7 to isolate x:
x = 3
Now we have solved for x in terms of the equation 7x = 15 + 6.
To check our solution, we can substitute x = 3 back into the original equation:
7(3) = 15 + 6
21 = 21
The equation is true, so our solution x = 3 is correct.