What is the value of y and x in the two equations .50x + .75y= 20 & x + y= 11.50. show me work , enjoy ur 30 points.

x = -45.5

y=57

Step-by-step explanation:

.50x + .75y= 20

x + y= 11.50

Multiply the second equation by -1/2 so we can eliminate x

-.5 (x + y= 11.50)

-.5x - .5 y = -5.75

Add this equation to the first equation

-.5x - .5 y = -5.75

.50x + .75y= 20

.25y = 14.25

Divide by .25

.25y/.25 = 14.25/.25

y =57

Now we still need to find x

x + y= 11.50

x + 57 = 11.5

Subtract 57 from each side

x+57-57 = 11.5-57

x = 45.5

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step-by-step explanation:

if the four friends split the cost, p, of the pizza evenly, then each friend pays one-fourth of the cost of the pizza.

the expression is   or