Answer:
x = 8, and y = 12
Step-by-step explanation:
There are 2 variables, so you need 2 equations to form a system of equations in two variables.
The upper left triangle has all angle measures given: 100, 2x + y, 5x + y. We know that the sum of the measures of the angles of a triangle is 180.
First equation:
100 + 2x + y + 5x + y = 180
Simplify:
7x + 2y = 80 (First equation)
Now we see that the upper and lower sides are parallel, so alternate interior angles are congruent. The angles measuring 2x + y and 5x - y are alternate interior angles and are congruent.
Second equation:
2x + y = 5x - y
Simplify:
3x - 2y = 0 (Second equation)
Now we use the first equation and the second equation as a system of simultaneous equations to solve for x and y.
7x + 2y = 80
3x - 2y = 0
Solve the second equation for 2x.
3x = 2y
Now replace 2y in the first equation with 3x.
7x + 3x = 80
10x = 80
x = 8
Replace x with 8 in the second equation.
3(8) - 2x = 0
24 = 2x
x = 12
Answer: x = 8, and y = 12
Answer:
A=πr2
Step-by-step explanation:
Answer:
x squared plus two times x minus one = zero.
Step-by-step explanation:
(This is a Quadratic equation in the variable x).
Answer:
Step-by-step explanation:
<h3>Given</h3>
<u>Quadratic function </u>
with the roots:
<h3>To find </h3>
<h3>Solution</h3>
<u>As we know the sum of the roots is -b/a and the product of the roots is c/a. Substituting values and solving for b and c:</u>
- (-5 + 9i) + (-5 - 9i) = -b/-1
- -10 = b
- b = -10
And
- (-5 + 9i)(-5 - 9i) = c/-1
- (-5)² - (9i)² = -c
- 25 - 81(-1) = -c
- - c = 25 + 81
- - c = 106
- c = -106
g(x) = -x² -10x - 106