Question

53. The measure of the supplement of an angle is 20 degrees more than three times the measure of the original angle. Find the measures of the angles.

So far I have:
s = 3a + 20
s + a = 180

Answer 1

I always get lost in the middle of working these out ;~;

Answer 2

Have you learnt simultaneous equations?

Answer 3

Because that is what you will need for this question

Answer 4

Yeah! I'm practicing them now. I just keep getting lost on where to go after writing an equation down.

Answer 5

RIP.

Answer 6

AGH I feel dumb, I swear every time I post these I have a lightbulb moment two minutes later

Answer 7

we can check your work then just to make sure you're on the right path :3

Answer 8

Wait, no, that's not gonna help me. I was doing it wrong and got s-20/3 = a, not much help. Should I make that into the 180 equation? Like, s + (s-20/3) = 180, or am I just digging myself into a deeper hole there?

Answer 9

Well, that could work

Answer 10

Carry on

Answer 11

you have the two equations correct

s = 3a + 20
s + a = 180

You can solve them by substitution

Answer 12

That is what he has started with @TheSmartOne

Answer 13

Yea! I reversed the first equation, sorta, so I had one variable to work with. I got an s answer so far of 330, so I'm about to plug that into s = 3a + 20 and try to work it out, and see how that goes.

Answer 14

That's also kind of a. Huge angle though. >n>;

Answer 15

So I think I def goofed somewhere along that line.

Answer 16

mhmm, yeah you did

you can plug in s = 3a + 20
in to s + a = 180


where we have s in the second equation, we can replace it with 3a + 20 since the first equation says that s is equal to 3a + 20

do you understand? :)

Answer 17

I'm gonna try that again w/ just the two variables. :V

Answer 18

OH. Yea, alright, geez, I was putting it in backwards. Silly me.

Answer 19

Try solving for the s again

Answer 20

I'm gonna try to solve for a, actually! Gimme just one sec.

Answer 21

yeah, if you substitute s = 3a + 20 in to the second equation, you'll be solving for a :)

Answer 22

Use TheSmartOne's idea of substituting s with 3a+20

Answer 23

That is if you want to solve for a

Answer 24

at the end, we need to solve for both variables so it doesn't matter which one we start with :)

Answer 25

I got 26.65. That's a lot more reasonable than freakin', 330, at least.

Answer 26

Buuuuut it's wrong, still

Answer 27

B(

Answer 28

What did you get for a?

Answer 29

Wait a tic, let me try something. I think I did some extra, unnecessary math, bc 26.65 is certainly Not it.

Answer 30

Nope, I was wrong either way ¯\_(ツ)_/¯

Answer 31

can you show us your work? :)

Answer 32

If the second equation is a+s=180, and you already know that s is 3a+20, put it as s in the equation a+s=180. Then work from there

Answer 33

Yea!

(3a+20) + a = 180
-20 -20
(3a) + a = 180
/3a /3a
a = 180/3

AND As I was typing that out I realized you can't... divide numbers like 180 by numbers w/ coefficients like that... (Right word? Who knows, not me.)

Answer 34

Look you subtracted 20 from both sides right? 180-20 isn't 180

Answer 35

ER RIGHT. I meant 160.

Answer 36

I have that written down I swear. Sorry, I was trying to type really fast. Anyways, I ended up with 53.3... which I know isn't right bc that's not even, like. A Number. It repeats forever.

Answer 37

and 3a + a = 4a

so you need to divide both sides by 4 to isolate a :)

Answer 38

You also should get to know that 3a+a=4a

Answer 39

OH That makes. A lot of sense

Answer 40

3a + a is the same thing as a(3 + 1) = a(4) = 4a

Answer 41

OK, I got 40! When I plug it in like this:
s= 3(40) + 20
s= 120 + 20
s= 140

And 140 + 40 is definitely 180. Success!

Answer 42

Also that's right. I sometimes forget that a number on its own is an implied 1. x')

Answer 43

well done :D

Answer 44

Thank you both for all your help!

Answer 45

It was my pleasure :)

Answer 46

Your welcome