So,
All you have to do is to translate the words into open sentences with placeholders.
Apparently, there are 2 numbers, call them x and y.
Now, build open sentences.
x + y = 12
x - y = 4
Now, which method will we use to solve? I choose Elimination by Addition.
Add the equations together.
2x = 16
Divide both sides by 2
x = 8
Substitute
8 + y = 12
Subtract 8 from both sides.
y = 4
Check
The sum of the two numbers is 12 (8 + 4).
The difference of the two numbers is 4 (8 - 4).
The first number is 8.
The second number is 4.
Answer:
in Desmos there should be a plus sign right above the list of your equations on the left side. Click that plus sign and then click "table". then enter your numbers. then your points will be shown on the graph
to turn this into a line long press on the button next "y" on the table you have made, then select "lines"
Perpendicular lines are lines that, when intersect the original line, form a right angle. This is formed when two lines' gradients are the negative reciprocals of each other.
In essence,
![m_1 \cdot m_2 = -1](https://tex.z-dn.net/?f=m_1%20%5Ccdot%20m_2%20%3D%20-1)
Now let 5 be
![m_1](https://tex.z-dn.net/?f=m_1)
Thus,
![5 \cdot m_2 = -1](https://tex.z-dn.net/?f=5%20%5Ccdot%20m_2%20%3D%20-1)
![m_2 = -\frac{1}{5}](https://tex.z-dn.net/?f=m_2%20%3D%20-%5Cfrac%7B1%7D%7B5%7D)
That means any line with a gradient or slope of
![-\frac{1}{5}](https://tex.z-dn.net/?f=-%5Cfrac%7B1%7D%7B5%7D)
is a line that is perpendicular to this line.
In essence, the general equation would be:
Answer:
C
Step-by-step explanation:
I can't understand what you'r saying because of the " A. B. C words" but the answer will be C 120(0.053) but since I can't understand the question i think it's this answer but next time can you make you'r question more easy to read.
Hope you understand....
A Quadrilateral A B C D in which Sides AB and DC are congruent and parallel.
The student has written the following explanation
Side AB is parallel to side DC so the alternate interior angles, angle ABD and angle BDC, are congruent. Side AB is equal to side DC and DB is the side common to triangles ABD and BCD. Therefore, the triangles ABD and CDB are congruent by SAS.
The student has also written
angles DBC and ADB are congruent and sides AD and BC are congruent. Angle DBC and angle ADB form a pair of alternate interior angles. Therefore, AD is congruent and parallel to BC. Quadrilateral ABCD is a parallelogram because its opposite sides are equal and parallel.
Postulate SAS completely describes the student's proof.
Because if in a quadrilateral one pair of opposite sides are equal and parallel then it is a parallelogram.