PLZ HELP ME ☻ Solve system of equations

Step-by-step explanation:

Let's re-write the equations in order to get the variables as separated in independent terms as possible \:

First equation:

Second equation:

Third equation:

Now let's subtract term by term the reduced equation 3 from the reduced equation 1 in order to eliminate the term that contains "y":

Combine this last expression term by term with the reduced equation 2, and solve for "x" :

Now we use this value for "x" back in equation 1 to solve for "y":

And finally we solve for the third unknown "z":

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.