Answer:
y=mx+b
Step-by-step explanation:
Circumference of a circle is C = 2πr.
part 1)
so the radius of the smaller gear is 3 inches, so after a full rotation, namely a revolution, the smaller gear has covered an arc of 2π(3), or 6π.
what angle has the larger gear of 7 inches in radius, has it covered with an arc of 6π?
part 2)
since the larger gear has a radius of 7, in a revolution it will have an arc of 2π(7), or 14π.
now, we know the smaller gear does a 6π arc in a revolution, how many revolutions will it do in an arc of 14π?
90-69=21 degrees. This is our target answer. We'll write an equation to do this:
2x-1=21
Add 1 to each side to get:
2x=22
Divide by 2 to get that x=11
Plugging this in, we see that 2(11)-1+69=90, so our answer is correct.
:)
Answer:
Step-by-step explanation:
x - 30 = 14 - 3x
4x = 44
x = 11
Let's call the unknown number x
Now let's decrease it by 30, that is x-30
Now let's write out "14 decreased by three times the number", that is 14 - 3x
The problem says these are the same, that is x - 30 = 14 - 3x
We now want to isolate, or solve for, x
Move the x to one side of the equation by adding 3x to both sides
3x + x -30 = 14 - 3x + 3x
4x -30 = 14
Now move the 30 to the right hand side by adding 30 to both sides
4x - 30 + 30 = 14 + 30
4x = 44
Now all we have to do to get x is divide both sides by 4
4x/4 = 44/4
x = 11
Answer:
B
Step-by-step explanation:
no explanation.......