First set up your two equations:
x + y = 90
x = 2y - 30
Then substitute what x equals in the second equation into the first equation:
(2y -30) + y = 90
Now solve for y:
3y -30 = 90
3y = 120
y = 40
Then use y = 40 and substitute the value for y into one of your original equations and solve for x. I'll choose the first one, but either one will work.
x+ 40 = 90
x = 50
So your solution is x = 50 and y = 40
Answer:
Regular Polygons
Polygons can also be classified as equilateral, equiangular, or both. Equilateral polygons have congruent sides, like a rhombus. Equiangular polygons have congruent interior angles, like a rectangle. When a polygon is both equilateral and equiangular, it is called a regular polygon.
Answer:
156.5
Step-by-step explanation:
Thinking process:
The area can be calculated using the formula:

We let the substitution take place.
Therefore, we let 
Thus, 
So,

Also, the interval of the integration changes to [ 37, 65]
Thus,

= 
= 156.5 units²
Answer:
140
Step-by-step explanation:
46+94 = 140
Make the denominator the same, so multiple 3/10 by 2, which produces 6/20. Take 6/20 and subtract 7/20 because adding a negative number is the same as subtracting a positive number. the Answer is -1/20.