Mel and Nancy both worked hard over the summer. Together they earned a total of $525. Mel earned $75 more than Nancy. Write a system of equations for the situation. Use M for the amount Mel earned and N for the amount Nancy earned.

M- 300

N- 225

Step-by-step explanation:

525 - 75 = 450

450/2= 225

225 + 75 = 300

225x²+4=0

225x²=0-4

225x²=-4

x²=-4/225

x=±√-4/225

a 4/6 = 9/12   not proportional

step-by-step explanation:

to find which are not proportional, we can use cross products

if it is true, they are proportional.   if it is not true, they are not proportional.

a 4/6 = 9/12

4* 12 = 6*9

48 = 54

not this is not proportional  

b 2/3 = 12/18  

2* 18 = 3 * 12

36 = 36

this is proportional

c 5/4 = 10/8  

5*8 = 4*10

40 = 40

this is proportional

d 7/5 = 35/25

7*25 = 5 * 35

175 = 175

is proportional