Solve 3x − 7 = 5

The solution of 3x − 7 = 5 is x = 4.

3x - 7 = 5\ \Rightarrow\ x = 4

Explain it step by step in chat Make a short video of it

The lines y = 3x − 7 and y = 5 meet at x = 4. The solution of the equation is the x-coordinate of the point where the two sides are equal.

How to work it out

1
The goal is to get x alone. Undo the operations in the opposite order: first the subtraction, then the multiplication.
$3x - 7 = 5$
2
Add 7 to both sides:
$3x - 7 + 7 = 5 + 7 \ \Rightarrow\ 3x = 12$
3
Divide both sides by 3:
$\frac{3x}{3} = \frac{12}{3} \ \Rightarrow\ x = 4$
4
Check: put x = 4 back into the equation.
$3\cdot4 - 7 = 12 - 7 = 5 \checkmark$

LaTeX source of the formulas on this page

\[ 3x - 7 = 5\ \Rightarrow\ x = 4 \]
\[ 3x - 7 = 5 \]
\[ 3x - 7 + 7 = 5 + 7 \ \Rightarrow\ 3x = 12 \]
\[ \frac{3x}{3} = \frac{12}{3} \ \Rightarrow\ x = 4 \]
\[ 3\cdot4 - 7 = 12 - 7 = 5 \checkmark \]

Trying values of x in 3x − 7 = 5

x	3x − 7	Equals 5?
2	-1	no
3	2	no
4	5	yes
5	8	no
6	11	no

Questions

What is x in 3x − 7 = 5?

The solution of 3x − 7 = 5 is x = 4.

How do you solve 3x − 7 = 5?

Add 7 to both sides to get 3x = 12, then divide both sides by 3 to get x = 4.

How do I check the answer?

Replace x by 4: 3(4) − 7 = 5, which is 5.

Solve 3x − 7 = 5

How to work it out

Trying values of x in 3x − 7 = 5

Questions

Similar equations