Need help on these 2 questions

y = -1 and x = 3

Step-by-step explanation:

x=-2y+6

3x-4y = 28

There are two ways to solve this:  1) solve directly with the equations, and 2) graph the line and look for the intersection.

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Use the definition of x from the first equation and substitute it in the second:

3x-4y = 28

3(-2y+6)-4y = 28

-6y + 18 -4y = 28

-10y = 10

y = - 1

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Graph the two lines and find the value of y at the point they intersect.  See the attachment.

y = -1 at x= 8

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For the second question:

y=3x-10

4x+5y=7

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4x+5y=7

4x+5(3x-10)=7

4x+15x-50=7

19x = 57

x = 3

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mr. flanders’ class sold 47 doughnuts and   mr. rodriquez’s class sold 38 cartons of milk

step-by-step explanation:

let x be the number of doughnuts sold by mr. flanders’ class and y be the number of cartons sold by mr. rodriquez’s class.

1. together, the classes sold 85 items, then

x+y=85.

2. both classes earn earned $104.49 for their school. if doughnuts were sold for $1.35 each, then x doughnuts costed $1.35x. if cartons of milk were sold for $1.08 each, then y cartons costed $1.08y. hence,

1.35x+1.08y=104.49.

3. solve the system of two equations:

x> 6

step-by-step explanation:

8x+8> 7x+14

8x-7x> 14-8

x> 6