Solve 7x − 14 = 126

The solution of 7x − 14 = 126 is x = 20.

7x - 14 = 126\ \Rightarrow\ x = 20

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

The lines y = 7x − 14 and y = 126 meet at x = 20. 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.
$7x - 14 = 126$
2
Add 14 to both sides:
$7x - 14 + 14 = 126 + 14 \ \Rightarrow\ 7x = 140$
3
Divide both sides by 7:
$\frac{7x}{7} = \frac{140}{7} \ \Rightarrow\ x = 20$
4
Check: put x = 20 back into the equation.
$7\cdot20 - 14 = 140 - 14 = 126 \checkmark$

LaTeX source of the formulas on this page

\[ 7x - 14 = 126\ \Rightarrow\ x = 20 \]
\[ 7x - 14 = 126 \]
\[ 7x - 14 + 14 = 126 + 14 \ \Rightarrow\ 7x = 140 \]
\[ \frac{7x}{7} = \frac{140}{7} \ \Rightarrow\ x = 20 \]
\[ 7\cdot20 - 14 = 140 - 14 = 126 \checkmark \]

Trying values of x in 7x − 14 = 126

x	7x − 14	Equals 126?
18	112	no
19	119	no
20	126	yes
21	133	no
22	140	no

Questions

What is x in 7x − 14 = 126?

The solution of 7x − 14 = 126 is x = 20.

How do you solve 7x − 14 = 126?

Add 14 to both sides to get 7x = 140, then divide both sides by 7 to get x = 20.

How do I check the answer?

Replace x by 20: 7(20) − 14 = 126, which is 126.

Solve 7x − 14 = 126

How to work it out

Trying values of x in 7x − 14 = 126

Questions

Similar equations