(96+92+80+91+86+x)= 90
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6
(445+x)=90
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6
then you multiply 6 on both sides
445+×=540
-445. -445
x= 95
they need a 95 percent to have an average of a 90%.
i dont have a favorite, but i like Blow My Phone Up, Hopeless, and Midnight Thoughts :3
1. first parabola is up, so a are going to be positive
y = a(x-r)(x-s),
roots -7,-3, so we can write y=a(x+7)(x+3) [1]
we can take point (-5,-2), substitute into equation [1], and find value of a
-2=a(-5+7)(-5+3)
-2=a*2*(-2)
a=1/2
so first parabola has an equation
y=1/2(x+7)(x+3)
2. second parabola
y=a(x-r)(x-s) roots are 2 and 4 so we ca write
y=a(x-2)(x-4) take point (3,4) and substitute into this equation
4 =a(3-2)(3-4)
4=-a
a=-4, and it will look down
y=-4(x-2)(x-4)
5 and 1 half this is the answer my son thought of.
1/5, 2/10, 3/15, 4/20, 5,25, and on going up a number example (...6,7,8,9,10) and up 5 example (...30,35,40,45)