That's the second one,
180 - x = r
Whenever two lines cross we get congruent opposite angles and supplemental adjacent angles, i.e. they add to 180 degrees.
The first one is almost right; we have r+y+z=180 and r+x=180 so x=y+z not quite what was written.
Answer: 5 times
Step-by-step explanation:
Let the number of times that he saved $75 be x.
Let the number of times that he saved $150 be y.
Therefore, based on the information given in the question, we can form an equation which will be:
x + y = 8 ...... i
75x + 150y = 825 ....... ii
From equation I,
x + y = 8
y = 8 - x....... iiii
Put equation iii into ii and this will be:
75x + 150y = 825
75x + 150(8 - x) = 825
75x + 1200 - 150x = 825
75x - 150x = 825 - 1200
-75x = -375
x = 375/75
x = 5
He saved $75 5times from his paycheck.