A quadratic equation is one in which the highest exponent of x is 2.

is quadratic; the highest exponent is 2.
x³-3x²+1=0 is NOT quadratic. The highest exponent of x is 3, not 2.
5x-7=0 is NOT quadratic. The highest exponent of x is 1, not 2.
x²+3x-5=0 is quadratic; the highest exponent of x is 2.
x-5=9x+7 is NOT quadratic. The highest exponent of x is 1, not 2.
x²-x=3x+7 is quadratic; the highest exponent of x is 2.
<span>Equation at the end of step 1 :</span> (2x - 5 • (2x - 7y + 3)) + -8<span> :</span>Pulling out like terms :3.1 Pull out like factors :
-8x + 35y - 23 = -1 • (8x - 35y + 23)
Final result : -8x + 35y - 23
Answer:
-21
Step-by-step explanation:
I assume this is a 2 by 2 matrix.

determinant = -5 * 4 - 1 * 1 = -20 - 1 = -21
I think it is C sorry if i am wrong but i am confident