Solve 10x − 15 = 155

The solution of 10x − 15 = 155 is x = 17.

10x - 15 = 155\ \Rightarrow\ x = 17

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

The lines y = 10x − 15 and y = 155 meet at x = 17. 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.
$10x - 15 = 155$
2
Add 15 to both sides:
$10x - 15 + 15 = 155 + 15 \ \Rightarrow\ 10x = 170$
3
Divide both sides by 10:
$\frac{10x}{10} = \frac{170}{10} \ \Rightarrow\ x = 17$
4
Check: put x = 17 back into the equation.
$10\cdot17 - 15 = 170 - 15 = 155 \checkmark$

LaTeX source of the formulas on this page

\[ 10x - 15 = 155\ \Rightarrow\ x = 17 \]
\[ 10x - 15 = 155 \]
\[ 10x - 15 + 15 = 155 + 15 \ \Rightarrow\ 10x = 170 \]
\[ \frac{10x}{10} = \frac{170}{10} \ \Rightarrow\ x = 17 \]
\[ 10\cdot17 - 15 = 170 - 15 = 155 \checkmark \]

Trying values of x in 10x − 15 = 155

x	10x − 15	Equals 155?
15	135	no
16	145	no
17	155	yes
18	165	no
19	175	no

Questions

What is x in 10x − 15 = 155?

The solution of 10x − 15 = 155 is x = 17.

How do you solve 10x − 15 = 155?

Add 15 to both sides to get 10x = 170, then divide both sides by 10 to get x = 17.

How do I check the answer?

Replace x by 17: 10(17) − 15 = 155, which is 155.

Solve 10x − 15 = 155

How to work it out

Trying values of x in 10x − 15 = 155

Questions

Similar equations