what should be subtracted from x square - 2 X Y + Y square minus x + Y + 3 to obtain - X square + 4 x y - 3 y square + 1

Solve this equation using substitution. {4x + y = −2} {4x + 6y = 44}

The measure of an angle is 117°. what is the measure of a supplementary angle?

Select the correct answer. what is the exact value of sin (157.5°)? a. 'sqrt(2 - sqrt(2))/2 b. *"-"'sqrt(2 + sqrt(2))/29 c.'sqrt(2 + sqrt(2))/4" d. "-"sqrt(2 + sqrt(2))/4)