16. would be C since they both consist of the same variable to the same power
17. x-2x+7-9+4x
c. 3x-2
18. -4(3a-5). You would multiply -4 by 3 a, and -4 by -5. It turns to
-4(3a)-4(-5)
a. -12a+20
Let m and s be the number of math and sociology books sold respectively.
m=s+88 we are also told that:
m+s=426, using m found above in this equation gives you:
s+88+s=426 combine like terms on left side
2s+88=426 subtract 88 from both sides
2s=338 divide both sides by 2
s=169, since m=s+88
m=169+88=257
So 257 math and 169 sociology textbooks were sold.
Answer:
7(x4) = 8-x
Step-by-step explanation:
Answer:
It weighs 40 pounds on mars
Step-by-step explanation:
Direct proportion is the relationship between two variables when their ratio is equal to a constant value
- It can be expressed as y = k x, where y varies directly as x and k is constant of variation
- It can be expressed as
∵ The weight of an object on mars varies directly as the weight
of the object on earth
∴ w(m) = k × w(e)
∵ The weight of the object on earth is 75 pound
∴ w(e) = 75
∵ The weight of this object on mars is 25 pounds
∴ w(m) = 25
- Substitute them in the equation of variation
∵ 25 = k × 75
- Divide both sides by 75
∴
= k
∴ w(m) =
× w(e)
∵ An object weighs 120 pounds on earth
∴ w(e) = 120
- Substitute it in the equation of variation
∴ w(m) =
× 120
∴ w(m) = 40
∴ It weighs 40 pounds on mars