The number of incorrect answers is 8.
<h3>What is a linear equation?</h3>
linear equation is an algebraic equation of the form y=mx+b. involving only a constant and a first-order (linear) term, where m is the slope and b is the y-intercept. Occasionally, the above is called a "linear equation of two variables," where y and x are the variables.
Let,
number correct of answer = x
number of incorrect answer = y
Given that,
Total number of answer x+y = 30 ......(1)
Total score = x-
y = 20 .......(2)
In equation (2) multiply by -1 on both side.
-x+
y = -20 .......(3)
Now,
Adding both the equation (1) and (3)
x+y-x+
y = 30-20
= 10
y = 8
Hence, The number of incorrect answers is 8.
To learn more about linear equation from the given link:
brainly.com/question/2226590
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