Answer:
I think its the third one
Step-by-step explanation:
1.
x + y = 5 ⇒ x = 5 - y
2(5 - y) - y = 7 (substitute)
10 - 2y - y = 7 (distribute)
10 - 3y = 7
-3y = -3 (subtraction)
y = 1(divide)
x + (1) = 5 (substitute then solve)
x = 4
2.
–4x – 6(–2x + 6) = 4 (substitute)
–4x + 12x – 36 = 4 (solve)
8x –36 = 4
8x = 40
x = 5
y = –2(5) + 6
y = –10 + 6
<span>y = –4
3.
3x + y = 7 </span>⇒ y = 7 - 3x
<span>-7x - 5(7 - 3x) = 25
-7x - 35 + 15x = 25
8x - 35 = 25
8x = 60
x = 7.5
y = 7 - 3(7.5)
y = 7 - 22.5
y = 15.5
4.
x + 3y = 9 </span>⇒ x = 9 - 3y
<span>2(9 - 3y) + 4y = 7
18 - 6y + 4y = 7
- 2y + 18 = 7
- 2y = -11
y = 5.5
x = 9 - 3(5.5)
x = 9 - 16.5
x = - 7.5</span>
4. 12
5. 15
6. 26
Those are the answers
The answer is <span>length = 10 yd, width = 2 yd
proof
</span><span>The length of the playground is 5 times longer than its width, it means
l=5w, but 10= 2x5 so we can write l= 5w,
and Area = 20 =l x w = (5x2) x 2 =20</span>
