<h2>
My Answer:</h2>
1 303.3$
Okay, I'm not 100% sure it's this because I suck at Math, but I'm 80% sure. I hope you do good on your assignment or test! ^^
A parabola is a quadratic function, and a quadratic can be expressed in vertex form, which is:
y=a(x-h)^2+k, where (h,k) is the vertex (absolute maximum or minimum point of the quadratic)
In this case we are given that (h,k) is (-5,80) so we have so far:
y=a(x--5)^2+80
y=a(x+5)^2+80, we are also told that it passes through the point (0,-45) so:
-45=a(0+5)^2+80
-45=25a+80 subtract 80 from both sides
-125=25a divide both sides by 25
-5=a, so now we know the complete vertex form is:
y=-5(x+5)^2+80
The x-intercepts occur when y=0 so:
0=-5(x+5)^2+80 add 5(x+5)^2 to both sides
5(x+5)^2=80 divide both sides by 5
(x+5)^2=16 take the square root of both sides
x+5=±√16 which is
x+5=±4 subtract 5 from both sides
x=-5±4 so the x-intercepts are:
x=-1 and -9
The associative property because you are moving the parentheses
Answer:
x = 1, y = -2
Step-by-step explanation:
15x + 3y = 9 (1)
10x + 7y = -4 (2)
3 × (2) - 2 × (1)
3 × (2)
30x + 21y = -12 (3)
2 × (1)
30x + 6y = 18 (4)
(3) - (4)
15y = -30
y = -30 / 15
y = -2
sub y = -2 into (1)
15x + 3y = 9
15x + (3 × -2) = 9
15x - 6 = 9
15x = 9 + 6
15x = 15
x = 15 / 15
x = 1