Solve 10x − 9 = 61

The solution of 10x − 9 = 61 is x = 7.

10x - 9 = 61\ \Rightarrow\ x = 7

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

The lines y = 10x − 9 and y = 61 meet at x = 7. 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.
$10x - 9 = 61$
2
Add 9 to both sides:
$10x - 9 + 9 = 61 + 9 \ \Rightarrow\ 10x = 70$
3
Divide both sides by 10:
$\frac{10x}{10} = \frac{70}{10} \ \Rightarrow\ x = 7$
4
Check: put x = 7 back into the equation.
$10\cdot7 - 9 = 70 - 9 = 61 \checkmark$

LaTeX source of the formulas on this page

\[ 10x - 9 = 61\ \Rightarrow\ x = 7 \]
\[ 10x - 9 = 61 \]
\[ 10x - 9 + 9 = 61 + 9 \ \Rightarrow\ 10x = 70 \]
\[ \frac{10x}{10} = \frac{70}{10} \ \Rightarrow\ x = 7 \]
\[ 10\cdot7 - 9 = 70 - 9 = 61 \checkmark \]

Trying values of x in 10x − 9 = 61

x	10x − 9	Equals 61?
5	41	no
6	51	no
7	61	yes
8	71	no
9	81	no

Questions

What is x in 10x − 9 = 61?

The solution of 10x − 9 = 61 is x = 7.

How do you solve 10x − 9 = 61?

Add 9 to both sides to get 10x = 70, then divide both sides by 10 to get x = 7.

How do I check the answer?

Replace x by 7: 10(7) − 9 = 61, which is 61.

Solve 10x − 9 = 61

How to work it out

Trying values of x in 10x − 9 = 61

Questions

Similar equations