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>
Answer:
D. 5-3x = 17
Step-by-step explanation:
The step carried out was subtracting 2 from both sides.

Answer:
i need the answer also
Step-by-step explanation:
So you are using Volume...
V=1/3(pi)r^2h
as you go thu this equation
15 x 15 =225
12 x12= 144
225-144= 81
81/9=9
which your piece would be 1/3 pi r^2h answer is 1356.48
and you round it to the nearest tenth. So
( 1356.5) is ur answer...... So (B)
I'll give you a hint. <u><em>This questions is about order of operations for pemdas. Its stand for: p-parenthesis, e-exponents, m-multiply, d-divide, a-add and s-subtract that came from left to right.</em></u>
First you had to calculate with exponents first.


Then you multiply and divide from left to right.





Final answer: 
Hope this helps!
And thank you for posting your question at here on brainly, and have a great day.
-Charlie