Solve 8x − 3 = 77

The solution of 8x − 3 = 77 is x = 10.

8x - 3 = 77\ \Rightarrow\ x = 10

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

The lines y = 8x − 3 and y = 77 meet at x = 10. 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.
$8x - 3 = 77$
2
Add 3 to both sides:
$8x - 3 + 3 = 77 + 3 \ \Rightarrow\ 8x = 80$
3
Divide both sides by 8:
$\frac{8x}{8} = \frac{80}{8} \ \Rightarrow\ x = 10$
4
Check: put x = 10 back into the equation.
$8\cdot10 - 3 = 80 - 3 = 77 \checkmark$

LaTeX source of the formulas on this page

\[ 8x - 3 = 77\ \Rightarrow\ x = 10 \]
\[ 8x - 3 = 77 \]
\[ 8x - 3 + 3 = 77 + 3 \ \Rightarrow\ 8x = 80 \]
\[ \frac{8x}{8} = \frac{80}{8} \ \Rightarrow\ x = 10 \]
\[ 8\cdot10 - 3 = 80 - 3 = 77 \checkmark \]

Trying values of x in 8x − 3 = 77

x	8x − 3	Equals 77?
8	61	no
9	69	no
10	77	yes
11	85	no
12	93	no

Questions

What is x in 8x − 3 = 77?

The solution of 8x − 3 = 77 is x = 10.

How do you solve 8x − 3 = 77?

Add 3 to both sides to get 8x = 80, then divide both sides by 8 to get x = 10.

How do I check the answer?

Replace x by 10: 8(10) − 3 = 77, which is 77.

Solve 8x − 3 = 77

How to work it out

Trying values of x in 8x − 3 = 77

Questions

Similar equations