Answer:
b is equal to negative a and a is also equal to negative b
Step-by-step explanation:
Step-by-step explanation:
If x = the amount of 12% and y = the amount of 20%, then x + y = 80
Since we need 80 grams of 15%, 80(.15) = 12.
We are given that .12x + .20y = 12.
We can solve the first equation for x or y. Let's do x.
x = 80 - y
.12(80 - y) + .20y = 12
9.6 - .12y + .20y = 12
.08y = 2.4
y = 30
x = 80 - 30 = 50
Answer: 98
Step-by-step explanation:
Area of four walls = Curved surface area
= perimeter × height
= 28 × 3.5
= 98 m square
