A little Algebra, and we're home free!
We are given R = 20 and r2 = 75. We need to find r1.
The formula is 1/R = 1/r1 + 1/r2. Plug-in:
1/20 = 1/r1 + 1/75
1/20 - 1/75 = 1/r1
0.0366 = 1/r1
r1 = 1/0.03666
r1 = 27.272
Our answer is r1 = 27 ohms.
Answer:
360 degrees in total.
Step-by-step explanation:
We are given that the m∠1 is 145 degrees, and because ∠1 and ∠2 form a straight line we can tell that 180-145 = 35.
So now here's what we know:
m∠1 = 145
m∠2 = 35
After that, we need to look at ∠5 and ∠6.
One thing we can notice right away is that ∠5 and ∠6 should measure the same as ∠1 and ∠2 (respectively) because they are corresponding angles.
Now we will add them all together to find the sum of all four angles.
m∠1 = 145 + m∠2 = 35 = 180
m∠5= 145 + m∠6 = 35 = 180
180 + 180 = 360