6y + 7 I don't know if that's what you're looking for
I believe the answer is 2.02
Answer:
{x = -3
, y=2 (Isolved for both variables be elimination)
Step-by-step explanation:
Solve the following system:
{3 x + 5 y = 1 | (equation 1)
7 x + 4 y = -13 | (equation 2)
Swap equation 1 with equation 2:
{7 x + 4 y = -13 | (equation 1)
3 x + 5 y = 1 | (equation 2)
Subtract 3/7 × (equation 1) from equation 2:
{7 x + 4 y = -13 | (equation 1)
0 x+(23 y)/7 = 46/7 | (equation 2)
Multiply equation 2 by 7/23:
{7 x + 4 y = -13 | (equation 1)
0 x+y = 2 | (equation 2)
Subtract 4 × (equation 2) from equation 1:
{7 x+0 y = -21 | (equation 1)
0 x+y = 2 | (equation 2)
Divide equation 1 by 7:
{x+0 y = -3 | (equation 1)
0 x+y = 2 | (equation 2)
Collect results:
Answer: {x = -3
, y=2
X = the number of months the tire was used
y = the thickness of the tire tread
y = -(3/7)x + 20
Substitute x for 20 (the number of months the tire was used) and solve for y.
The next question: Substitute x for 49 (the number of months the tire was used) and solve for y.
Answer:
27 gallons
Step-by-step explanation:
If for every 41 miles, 3 gallons are needed. Using what we know, 369 ÷ 41 = 9. This means, to get 369 miles, we need to times the first amoiyng of gallons needed to drive 41 miles, which is 3, and times it by 9. (3×9=27) Therefore, 27 gallons of gas is needed.