Step-by-step explanation:
the vertex is the point, where the parabola turns around. it is (depending on its orientation, if it is opening upwards or downwards) the maximum or the minimum of the curve.
so, as we can see on the grid, that point is x = -3, y = +1 = (-3, 1).
so, B is correct
A suitable graphing caculator gives the result
X = 15 25/39
Y = 7 6/13
Z = 4 4/39
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If you want to solve this by hand, you can add 3 times the first equation to the second to get
... 5X -2Z = 70
and 5 times the first equation to the third to get
... 8X -11Z = 80
Then Cramer's Rule tells you the solutions for X and Z are
... X = (-160+770)/(-16+55) = 610/39
... Z = (560 -400)/39 = 160/39
From there, you can substitute into any of the equations to find Y. The first one might be most convenient.
... Y = 19 -X +Z = 19 -(15 25/39) +(4 4/39) = 8 -21/39 = 7 6/13
6 and 30 camd be simplified with 6
the result will be 1:5
so the question mark is 5
~ Simplifying
-2(7x + -5) = -14x + 10
~ Reorder the terms:
-2(-5 + 7x) = -14x + 10
(-5 * -2 + 7x * -2) = -14x + 10
(10 + -14x) = -14x + 10
~ Reorder the terms:
10 + -14x = 10 + -14x
~ Add '-10' to each side of the equation.
10 + -10 + -14x = 10 + -10 + -14x
~ Combine like terms: 10 + -10 = 0
0 + -14x = 10 + -10 + -14x
-14x = 10 + -10 + -14x
~ Combine like terms: 10 + -10 = 0
-14x = 0 + -14x
-14x = -14x
~ Add '14x' to each side of the equation.
-14x + 14x = -14x + 14x
~ Combine like terms: -14x + 14x = 0
0 = -14x + 14x
~ Combine like terms: -14x + 14x = 0
0 = 0
~ Solving
0 = 0
~ This equation is an identity, all real numbers are solutions.
