Answer:
Step-by-step explanation:
<u>Use distance formula:</u>
- d = st, where d- distance, s - speed, t - time
a)
<u>Total distance is:</u>
<u>Solve for x:</u>
- 8x = 70 - 10y
- x = (70 - 10y)/8 = (35 - 5y) / 4
<u>Solve for y:</u>
- 10y = 70 - 8x
- y = (70 - 8x) / 10 = (35 - 4x) / 5
b)
<u>Average speed is:</u>
- s(av) = d / t = 70 / (x + y)
c)
<u>The second scenario:</u>
<u>Combine with the first one and solve the system:</u>
<u>Solve by elimination as below:</u>
- 5(10x + 8y) - 4(8x + 10y) = 5*72 - 4*70
- 50x + 40y - 32x - 40y = 360 - 280
- 18x = 80
- x = 40/9
<u>Find y:</u>
- 10*40/9 + 8y = 72
- 8y = 72 - 400/9
- 8y = 248/9
- y = 31/9
140
The area is lengthX width so (7+7)(5+5) which is just 14 x 10
Answer:
36
Step-by-step explanation:
The first step to solving this equation is multiplying. Multiply the numbers on the inside of the square root.
18 × 18 × 4 = 1296
Now, you are going to find the square root of 1296.
= 36
You now have your final answer.
I hope this makes sense and is easy to understand. Please let me know if you need any more help. Have a great day! :]
Answer:
B
Step-by-step explanation:
Answer:
x=3 and y=1
Step-by-step explanation:
subtract equation 2 from 1
then (2x+3y) -(2x+y) =9-7
2x-2x+3y-y =2
2y=2 therefore y=1
substitute y value in 2x+y=7
2x+1=7
2x=7-1
2x=6
x=3