Answer:
standard form for a quadratic expression
Step-by-step explanation:
This is a quadratic expression. If you want this expression in standard form, write the terms in descending order of powers of x: -2x^2 + 1.
This -2x^2 + 1 has not yet been factored.
-2x^2 + 1 is in standard form.
-4x - 5y = 7
3x + 5y = -14
You can add these two equations together straightaway since the y-terms have opposite coefficients.
-4x - 5y = 7
3x + 5y = -14
+___________
-x - 0 = -7
-x = -7
x = 7
Substitute 7 for x into either of the original equations and solve algebraically to find y.
3x + 5y = -14
3(7) + 5y = -14
21 + 5y = -14
21 = -14 - 5y
35 = -5y
-7 = y
Finally, check work by substituting both x- and y-values into both original equations.
-4x - 5y = 7
-4(7) - 5(-7) = 7
-28 + 35 = 7
7 = 7
3x + 5y = -14
3(7) + 5(-7) = -14
21 - 35 = -14
-14 = -14
Answer:
x = 7 and y = -7; (7, -7).
Answer:13
Step-by-step explanation:
1. 2/3 - (1/4)*(4/9)
2/3-4/36
24/36-4/36
20/36 also same as 4/9 (D)
2. It's B. (-3*(2*7)=(-3*2)*7
3. -4+(-6)*(-3)
-4+18
-14 (b)
