For this case we must propose an algebraic expression associated with:
"four times a difference of a number and seven is 12"
So we have to:
Four times a difference of a number and seven is represented as: 
So we have the expression is:
We apply distributive property to the terms within parentheses:
We add 28 to both sides:
We divide between 4 on both sides:
Answer:
2,4 is the correct coordinates
1 7/10 can be rewritten as 1.7
51 / 1.7 = 30 plants.
<span>Rosalie has 30 plants.
</span>
We have that
<span>question 1
Add or subtract.
4m2 − 10m3 − 3m2 + 20m3
=(4m2-3m2)+(20m3-10m3)
=m2+10m3
the answer is the option
</span><span>B: m2 + 10m3
</span><span>Question 2:
Subtract. (9a3 + 6a2 − a) − (a3 + 6a − 3)
=(9a3-a3)+(6a2)+(-a-6a)+(-3)
=8a3+6a2-7a-3
the answer is the option
</span><span>B: 8a3 + 6a2 − 7a + 3
</span><span>Question 3:
A company distributes its product by train and by truck. The cost of distributing by train can be modeled as −0.06x2 + 35x − 135, and the cost of distributing by truck can be modeled as −0.03x2 + 29x − 165, where x is the number of tons of product distributed. Write a polynomial that represents the difference between the cost of distributing by train and the cost of distributing by truck.
we have that
[</span>the cost of distributing by train]-[the cost of distributing by truck]
=[−0.06x2 + 35x − 135]-[−0.03x2 + 29x − 165]
<span>=(-0.06x2+0.03x2)+(35x-29x)+(-135+165)
=-0.03x2+6x+30
the answer is the option
</span><span>C: −0.03x2 + 6x + 30
</span><span>
</span>
