Solve the following system algebraically

5x+3y=80
-2x+30=y

x = 10, y = 10 is the solution for the given system of equations.

Step-by-step explanation:

Here, the given set of equation are:

5 x + 3 y =  80

and -2 x + 30 = y

Here, substitute the value of y  =  -2x +  30 in equation (1)

Now, 5 x + 3 y =  80 ⇒  5x + 3( -2x +  30 )  =  80

or,  5x  -6x + 90  = 80

or, -x + 90 = 80

or, x = 90 - 80

⇒  x =  10

Now, y =  -2x + 30 = -2(10) + 30

                               = -20 + 30

                               = -20 + 30 = 10

⇒ y = 10

hence, x = 10, y = 10 is the solution for the given system of equations.

the answer is c: divide the arc's degree measure by 360°, then multiply by the circumference of the circle.