Answer:
The answer is<u> 2)a=−2</u>
Answer:
Step-by-step explanation:
i could try and help you but math is really confusing
Answer:Objective: Solve systems of equations with three variables using addition/elimination.
Solving systems of equations with 3 variables is very similar to how we solve systems with two variables. When we had two variables we reduced the system down
to one with only one variable (by substitution or addition). With three variables
we will reduce the system down to one with two variables (usually by addition),
which we can then solve by either addition or substitution.
To reduce from three variables down to two it is very important to keep the work
organized. We will use addition with two equations to eliminate one variable.
This new equation we will call (A). Then we will use a different pair of equations
and use addition to eliminate the same variable. This second new equation we
will call (B). Once we have done this we will have two equations (A) and (B)
with the same two variables that we can solve u
Step-by-step explanation:
Answer:
d) 135º
Step-by-step explanation:
Note that the angle DCU is the sum of the angles DCB and BCU. The angle DCB is 90º because A B C D is a square, then all its angles are equal to 90º.
After attaching B U C to A B C D, we obtain a trapezoid A U C D. Since A U C D has at least one pair of parallel sides, then AU should be parallel to CD, thus the angle CBU must be 90º.
B U C is isoceles, so we conclude that other two angles must have the same size, and due to the sum of the angles of a triangle being 180º, then both BUC and BCU are equal to 45º
As a result, the angle DCU is equal to 90º+45º = 135º. Option d is the correct one.
Answer:
y = 218
Step-by-step explanation:
Mean = (Sum of all numbers)/(How many numbers present)
27 = (20 + 2y + 25 + y + 30)/27
27 = (3y + 75)/27
3y + 75 = 729
3y = 729 - 75
3y = 654
y = 218
