Solve the system algebraically
x+3y=11
4x-4y=7

x = 65/16,   y = 37/16

Step-by-step explanation:

solve the system algebraically

x+3y=11

4x-4y=7

Try substitution.

let  x =  11 - 3y

Plug in.

4(11 - 3y) - 4y = 7

44 - 12y - 4y = 7

44 - 16y = 7

37 = 16y

y = 37/16

x = 11 - 3*y

x = 11 - 3*(37/16)

x = 11 -  111/16

x = 65/16

addition

step-by-step explanation:

b. 1.25 hr

step-by-step explanation:

if you have a constant speed of 60 mph, then you have a ratio between 60 mi. to 1 hr. dividing both sides by 60 we get the ratio

1 mi. to

then mult. both sides by 75 we get the ratio

75 mi. to

simplifying we get

75 mi. to

or 1.25 hr.