(please open my photo for reference as you read, I am a visual learner/explainer so it will make the most sense that way)
So the first thing you want to do is look at the exterior angle 130°. A straight line is 180°, and every Triangle's angular sum is 180°. How I think of it is that every straight line has a mini protractor on either side. It makes it a bit easier to understand.
180 - 130 = 50
You now know that two of the angles are 50°.
You now have two of the measurements for the triangle farthest to the left.
75° and 50°
75 + 50 = 125
180 - 125 = 55
a = 55°
Now that you have all the measurements for the first triangle, let's move onto the next one.
With two measurements for the second triangle, all you need to do is find their sum and subtract that from 180 and you will have the third measurement!
50 + 60 = 110
180 - 110 = 70
b = 70°
Finally, for the last triangle, you already have two of the measurements 60° and 85°.
85 + 60 = 145
180 - 145 = 35
c = 35°
Sorry if this explanation is a bit messy, it's hard to describe certain things without a letter or some kind of name to differentiate between them verbally.
I hope this helps! <3
Answer:
A.
Step-by-step explanation:
The Elimination Method is the method for solving a pair of linear equations which reduces one equation to one that has only a single variable.
If the coefficients of one variable are opposites, you add the equations to eliminate a variable, and then solve.
If the coefficients are not opposites, then we multiply one or both equations by a number to create opposite coefficients, and then add the equations to eliminate a variable and solve.
When multiplying the equation by a coefficient, we multiply both sides of the equation (multiplying both sides of the equation by some nonzero number does not change the solution).
So, option B is not allowed (it is not allowed to multiply only one part of the equation)
Answer:
Step-by-step explanation:
Because vertical angles are always equal, we want to solve 
.
We can add 10 to both sides to get 
.
We can subtract 
from both sides to get 
.
Lastly, we divide both sides by 20 to get 
.
So, 
and we're done!
The check is left as an exercise to the reader.
Once you complete the square, the simplified version of this equation is
(2x - 1)^2= 0
If you want to solve for x, subtract 1 and divide by 2.
x = 0.5
Answer:
557.28
Step-by-step explanation:
since it is a refund you subtract the amount due from the amount paid to get 2700.27 - 2142.99 = 557.25
