Answer:
-4
Step-by-step explanation:
Ok so you get two sets of proportional pairs: -3 and -1 , and -30 and -10.
The relationship between these is that the first term is 3 times the second. So you divide the first term by 3 to get the second.
So you divide -12 by 3 to get -4.
Hope this helps!
To find the decimal form of 12/20, we do:
12/20= 0.6
There are many ways of solving a system of equation, a very used one is by elimination of variables, which consists in eliminating one of the variables by combining the equations.
Let's do the following combination: (eq 1) + (eq 2)
This means that we add each term vertically:
⇒
When I said "add vertically" means that you add the first term of the first equation with the first term of the second equation. The second term of the first equation with the second term of the second equations, and so on.
This allowed us to remove the "y" temporarily so we can get a linear one-variable equation we can easily solve:
Now that we know the value of "x", we can plug it in any of the starting equations and get "y":
Therefore, our answer looks like this:
The measure of angle 1 and 2 should add up to 180°, because it forms a straight line. The same goes for the sum of angle 3 and 4.
Since we are given the measure of angle 2, we can find the measure of angle 1 by subtracting 143° from 180°.
180°-143° = 37°
We know that the intersecting lines form 2 sets of vertical angles, which are congruent. This means that the angles opposite from each other have the same measure. Therefore, both angle 2 & 4 have a measure of 143°, while angle 1 & 3 have a measure of 37°.