It’s definitely-20
Add 9 to both sides to cancel it out so it is now
4x-20=5x
Than subtract 4x on both sides it is now
-20=x
Because 5-4 equals 1 and 1x is just written as x
Answer:
b. 7x3 + 9x2 - 3x - 8
Step-by-step explanation:
Write the problem as a mathematical expression.
(4x3+6x2+2x−3)+(3x3+3x2−5x−5)
Remove parentheses.
4x3+6x2+2x−3+3x3+3x2−5x−5
Add 4x3
and 3x3
.
7x3+6x2+2x−3+3x2−5x−5
Add 6x2
and 3x2
.
7x3+9x2+2x−3−5x−5
Subtract 5x
from 2x
.
7x3+9x2−3x−3−5
Subtract 5
from −3
.
7x3+9x2−3x−8
Assume you need x liters 10% acid, y liters 80% acid
Then 10%x + 80%y = 65%*70, and x+y = 70
I get: x = 15, y = 55
What does part a mean i dont understand