You first have to start with an equation. Let's take what we know.
Megan has 31 points
To get 31, you have to enter in all the other information we know.
Megan's score is -7pts and 2 times Kara's points.
The equation would be: 31= 2k-7
Now you have to find the value of k. Start off by adding 7 to both sides of the equation because addition is the opposite operation of subtraction.
31=2k-7
+7 +7
38=2k
Now divide by 2 on both sides because division is the opposite operation of multiplication. You need to isolate* the variable(k)
38=2k
÷2 ÷2
19=k
The answer is that Kara scored 19 points. To make sure this is correct, substitute the variable,k, for 19. If the numbers are the same on both sides of the equals sign, the answer is correct.
*isolate also means to make something be alone/ by itself