Answer:
x = -4; y = -3
Step-by-step explanation:
2x - 5y = 7
3x - y = -9
Rewrite top equation. Multiply both sides of bottom equation by -5. Add equations. This eliminates y, and we solve for x.
2x - 5y = 7
(+) -15x + 5y = 45
----------------------------
-13x = 52
Divide both sides by -13.
x = -4
Substitute -4 for x in the first original equation and solve for y.
2x - 5y = 7
2(-4) - 5y = 7
-8 - 5y = 7
-5y = 15
y = -3
Answer: x = -4; y = -3
-5 =
Answer:
The answer is A.
Step-by-step explanation:
A because radius is half of the diameter
x = 8
Solution:
Side-splitter theorem:
<em>If a line is parallel to one side of a triangle and the line intersects the other two sides, then this line divides those two sides proportionally.</em>
Do cross multiplication, we get
⇒ 4 × 42 = 21x
Divide by 21 on both sides, we get
⇒ 4 × 2 = x
⇒ 8 = x
Switch the sides.
⇒ x = 8
The value of x is 8.
In order to get an 81 average,
the student has to get 81x5=405
71+96+90+73+?=405
330+?=405
405-330=75
he needs to get an 75
