Elimination:
7x - 3y = 20
5x + 3y = 16
(add)
12x = 36
÷ 12
x = 3
(5 × 3) + 3y = 16
15 + 3y = 16
- 15
3y = 1
÷ 3
y = 1/3
Substitution:
5x + 3y = 16
- 3y
5x = 16 - 3y
÷ 5
x = 3.2 - 0.6y
5(3.2 - 0.6y) + 3y = 16
16 - 3y + 3y = 16
16 = 16
- 16
6y = 0
÷ 6
y = 0
Sorry the substitution messed up for some reason, I'll fix it after I've answered the other question
It means that 15 times another number equals to your equation.
Answer:
264 miles
Step-by-step explanation:
Find the unit rate (mpg):
66 miles
----------------- = 22 mpg
3 gallons
On 12 gallons he could drive (22 mpg)(12 gallons) = 264 miles
Answer: 3.75
Step-by-step explanation:
8x - 7 = 3x + 9
8x - 3x = 9 + 7
5x = 16
x = 16/5 = 3 1/5
