7 books with a cost of 28$ then a 2$ charge which will put him right at 30
Step-by-step explanation:
<em>Combine like terms</em>
a. 2r + 3 + 4r = (2r + 4r) + 3 = 6r + 3
b. 8 + 3d + d = (3d + d) + 8 = 4d + 8
c. mn + (-3mn) + 6 = (mn - 3mn) + 6 = -2mn + 6
d. 10s + (-10) + (-4s) = (10s - 4s) - 10 = 14s - 10
<em>Terms are called "like terms" if they have the same variable part (the same letters in the same powers). Like terms differ at most coefficient.</em>
By graphing the polynomial, we conclude that there is only one real root, so the correct option is A.
<h3>
How many roots has the given polynomial?</h3>
We have the polynomial:

To see how many real roots this polynomial has, we can graph it and see how many times the graph intercepts the x-axis.
The graph can be seen below:
There we can see that there is only one intercept, so there is only one real root.
So the correct option is A.
If you want to learn more about polynomials:
brainly.com/question/4142886
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