11) -x + y = -1 ; 2x - y = 0
y = -1 + x ; 2x - (-1+x) = 0 ⇒ 2x + 1 - x = 0 ⇒x = -1
y = -1 + (-1) ⇒ y = -2
12) -2x + y = -20 ; 2x + y = 48
y = -20 + 2x ; 2x + (-20 + 2x) = 48 ⇒ 2x -20 + 2x = 48 ⇒ 4x = 48 + 20
4x = 68 ⇒ x = 68/4 ⇒ x = 17
y = -20 + 2(17) ⇒ y = -20 + 34 ⇒ y = 14
13) 3x -y = -2 ; -2x + y = 3
y = 3 + 2x ; 3x - (3 + 2x) = -2 ⇒ 3x - 3 - 2x = -2 ⇒ x = -2 + 3 ⇒ x = 1
y = 3 + 2(1) ⇒ y = 3 + 2 ⇒ y = 5
14) x - y = 4 ; x - 2y = 10
x = 4 + y ; (4 + y) - 2y = 10 ⇒ 4 + y - 2y = 10 ⇒ 4 - y = 10
⇒ -y = 10 - 4 ⇒ -y = 6 ⇒ y = -6
x = 4 + (-6) ⇒ x = 4 - 6 ⇒ x = -2
15) x + 2y = 5 ; 3x + 2y = 17
x = 5 - 2y ; 3(5-2y) + 2y = 17 ⇒ 15 - 6y + 2y = 17 ⇒ -4y = 17 - 15
⇒ -4y = 2 ⇒ y = -2/4 ⇒ y = -1/2
x = 5 - 2(-1/2) ⇒ x = 5 + 2/2 ⇒ x = 5 + 1 ⇒ x = 6
Answer:
28 square units.
Step-by-step explanation:
This is a rectangle with sides (7 - (-7) and (5 - 3)
= 14 by 2
= 28 unit^2.
Answer: I feel ike it should be C
Step-by-step explanation:
I just guessed
:)
<span>I believe you MEANT 8/(x^2-25)+9/(x-5) Parentheses in this format are important...the way you typed it means (8/x^2)-25+(9/x)-5 which I doubt you mean. Anyway.
If you factor the first denominator you will see that it is equal to (x+5)(x-5). Division by zero has no meaning so x cannot equal -5 or 5.
If we multiply the second fraction by (x+5) we will have a common denominator of (x^2-25) for the entire equation leaving us with:
(8+9x+45)/(x^2-25)
(9x+53)/(x^2-25)
The second problem is worked in exactly the same way, notice that there is no "solution" as there is no equal sign. This is an "expression" not an "equation".</span>
