We have that
<span>4x -2y =22------> clear variable y
2y=4x-22--------> y=4x/2-22/2---------> y=2x-11-----> equation 1
2x + 4y = 6------> equation 2
substitute equation 1 in equation 2
2x+4*[2x-11]=6-----> 2x+8x-44=6----> 10x=50------> x=5
then
y=2x-11----> y=2*5-11----> y=-1
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1. C - You could add 6 and divide by negative three with this one
2. B - By plugging in five, you would get 9-10. and that would give you -1
3. B - You would add 18 to 12 to get 30
Y=cos(2x+pi) - 2
y= - cos(2x) - 2
{ Since cos(x+pi) =-cos(x)}