Solve 8x − 15 = 49

The solution of 8x − 15 = 49 is x = 8.

8x - 15 = 49\ \Rightarrow\ x = 8

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

The lines y = 8x − 15 and y = 49 meet at x = 8. 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.
$8x - 15 = 49$
2
Add 15 to both sides:
$8x - 15 + 15 = 49 + 15 \ \Rightarrow\ 8x = 64$
3
Divide both sides by 8:
$\frac{8x}{8} = \frac{64}{8} \ \Rightarrow\ x = 8$
4
Check: put x = 8 back into the equation.
$8\cdot8 - 15 = 64 - 15 = 49 \checkmark$

LaTeX source of the formulas on this page

\[ 8x - 15 = 49\ \Rightarrow\ x = 8 \]
\[ 8x - 15 = 49 \]
\[ 8x - 15 + 15 = 49 + 15 \ \Rightarrow\ 8x = 64 \]
\[ \frac{8x}{8} = \frac{64}{8} \ \Rightarrow\ x = 8 \]
\[ 8\cdot8 - 15 = 64 - 15 = 49 \checkmark \]

Trying values of x in 8x − 15 = 49

x	8x − 15	Equals 49?
6	33	no
7	41	no
8	49	yes
9	57	no
10	65	no

Questions

What is x in 8x − 15 = 49?

The solution of 8x − 15 = 49 is x = 8.

How do you solve 8x − 15 = 49?

Add 15 to both sides to get 8x = 64, then divide both sides by 8 to get x = 8.

How do I check the answer?

Replace x by 8: 8(8) − 15 = 49, which is 49.

Solve 8x − 15 = 49

How to work it out

Trying values of x in 8x − 15 = 49

Questions

Similar equations