8/10 = 16/y How do I do this by cross multiply
1 answer:
You might be interested in
Answer:
Option B.
Step-by-step explanation:
The given expression is
We need an expression Which represents the same solution as the given expression.
It can be written as
Since is equivalent to given equation, therefore this equation represents the same solution as the given expression.
Hence, option B is correct.
See the attached diagram, it has all the information you need.
(a) If the green radii are all 1, then the orange diameters are all 2 + √2, so that the orange radii are (2 + √2)/2 = 1 + √2/2.
This is because we can join the radii of two adjacent green circles to form the sides of a square with side length equal to twice the radius - i.e. the diameter - of the green circles. The diagonal of any square occurs in a ratio to the side length of √2 to 1. Then we get the diameter of an orange circle by summing this diagonal length and two green radii, and hence the radius by dividing this by 2.
(b) We get the blue diameter in the same way. It has length (2 + √2) (1 + √2/2) = 3 + 2√2, so that the blue radius is (3 + 2√2)/2 = 3/2 + √2.
For this problem, you have to come up with two equations, one for each plan, and set them equal to each other to solve for how many minutes <span>of calls when the costs of the two plans are equal. Let's call the number of minutes "x." Remember the equation for slope-intersect form is:
</span>
<span>And we're trying to put in values for m and b.
So the first plan has a </span>$29 monthly fee and charges an additional $0.09 per minute. The $29 monthly fee will be our "b" in our slope-intersect equation because it won't be affected by our minutes "x." That means 0.09 is our "m" value because it will change with "x." So our equation for plan 1 is:
The second plan <span>has no monthly fee but charges 0.13 for each minute of calls. Because there is no monthly fee, there is no "b" this time. "m" will be 0.13. So our equation for plan 2 is"
</span>
Now we set our two equations equal to each other. "y" in the equation stands for the total cost of the plan. If the total costs are equal, then they have to be the same number, so we can put one of the equations for "y" into the other equation and solve for "x," our number of minutes:
</span>
<span>And we're trying to put in values for m and b.
So the first plan has a </span>$29 monthly fee and charges an additional $0.09 per minute. The $29 monthly fee will be our "b" in our slope-intersect equation because it won't be affected by our minutes "x." That means 0.09 is our "m" value because it will change with "x." So our equation for plan 1 is:
The second plan <span>has no monthly fee but charges 0.13 for each minute of calls. Because there is no monthly fee, there is no "b" this time. "m" will be 0.13. So our equation for plan 2 is"
</span>
Now we set our two equations equal to each other. "y" in the equation stands for the total cost of the plan. If the total costs are equal, then they have to be the same number, so we can put one of the equations for "y" into the other equation and solve for "x," our number of minutes: