Answer:
Let's simplify
24−7(n−2)(2115)
Step-by-step explanation:
step-by-step.
=−14805n+29634
I hope my answer helped
2 tens & 15 ones is equal to 35
Because 2 tens = 20
15 already has a ten so add +10 to 20
30+5 is 35.
Answer:
Perimeter = 60
Step-by-step explanation:
because l bisects AB:
3y+1 = 5y-5
reduce:
2y = 6
y = 3
and:
2x+4 = 4x-12
reduce:
2x = 16
x = 8
AB = (3y+1) + (5y-5)
AB = 8y-4
substitute for y
AB = 8(3)-4
AB = 20
Perimeter = (2x+4) + (4x-12) + 20
reduce:
perimeter = 6x+12
substitute for x:
Perimeter =6(8)+12
reduce:
Perimeter = 60
Answer:
Lots of "ifs" here.
A=bh/2 is the formula for the area of a triangle.
A=bh is the formula for the area of a rectangle or a parallelogram.
If the 6 & 4 area the base & height of a rectangle, then (6)(4) = 24 in^2
If the 6 & 10 are the base and height of a triangle, then 1/2(6)(10) = 30 in^2
Step-by-step explanation:
OK, so the graph is a parabola, with points x=0,y=0; x=6,y=-9; and x=12,y=0
Because the roots of the equation are 0 and 12, we know the formula is therefore of the form
y = ax(x - 12), for some a
So put in x = 6
-9 = 6a(-6)
9 = 36a
a = 1/4
So the parabola has a curve y = x(x-12) / 4, which can also be written y = 0.25x² - 3x
The gradient of this is dy/dx = 0.5x - 3
The key property of a parabolic dish is that it focuses radio waves travelling parallel to the y axis to a single point. So we should arrive at the same focal point no matter what point we chose to look at. So we can pick any point we like - e.g. the point x = 4, y = -8
Gradient of the parabolic mirror at x = 4 is -1
So the gradient of the normal to the mirror at x = 4 is therefore 1.
Radio waves initially travelling vertically downwards are reflected about the normal - which has a gradient of 1, so they're reflected so that they are travelling horizontally. So they arrive parallel to the y axis, and leave parallel to the x axis.
So the focal point is at y = -8, i.e. 1 metre above the back of the dish.
