Question

What does this equal? -1/5a+21=23​

Answer 1

Supposing you want this equation to be solved for a: we start with

$-\dfrac{a}{5}+21=23$

Subtract 21 from both sides:

$-\dfrac{a}{5}=2$

Multiply both sides by 5:

$-a=10$

Change sign to both sides:

$a=-10$

Answer 2

First substitute 21 to the right side
Then,
-1/5a=23-21
-1/5a=2
Now,take -1/5 to the other side
a=2(-5)
a=-10
Therefore,a should be substituted by -10 to make them equal.