Question

(1) Solve this system using the elimination method: a – 4b = 2; 5a = 3b - 7 (2) Solve this application problem using a system of equations: Discount Rental Cars charges a daily fee plus a mileage fee for renting its cars. Barney was charged $145.00 for 3 days and 310 miles, while Mary was charged $250.00 for 5 days and 600 miles. What does Discount Rental Cars charge per day and per mile? I would like these problems written out to in how the answer was solved.

Answer 1

Answer:

(1)- The given equations are

a-4b=2 ..... (1)

& 5a=3b -7

5a-3b= -7 ..... (2)

Multiplying by 5 in equation (1),we get

5(a-4b)= 2(5)

5a-20b=10 ...... (3)

FOR ELIMINATION METHOD, We Have

Subtracting equation (3) from (2),we get

(5a-3b)-(5a-20b)= (- 7)-10

5a - 3b-5a+20b= - 17

17b = -17

b= - 17/17

b= - 1

Put b= - 1 in equation (1), we get

a-4(-1)=2

a+4 = 2

a=2-4

a= - 2

Hence, ( a= - 2) &( b= - 1) is the solution of the given equation.