Answer:
(5,9)
Step-by-step explanation:
3y=4x+7
5y=4x+25
Subtract the two equations to eliminate x
5y=4x+25
-( 3y=4x+7)
------------------
2y = 0x +18
Divide by 2
2y/2 = 18/2
y =9
Now find x
3y = 4x+7
3*9 = 4x+7
27 = 4x+7
Subtract 7
20 = 4x
Divide 4
20/4 = 4x/4
5 =x
(5,9)
<span>Let x = the miles Jeanie ran
y = the miles Jeanie biked
T = 2 hours total time for the duathlon
v1 = 8.5 mph Jeanie's running speed and
v2 = 16 mph Jeanie's biking speed
But T = Jean's time she ran t1 + time she biked t2 I. e t1 + t2 = 2
So we have average speed v2 when she biked = distance (y) / time (t2)
Distance y = v2 * t2 = 16 * t2 and distance when she ran x = 8.5 * t1
Since she covered 27 miles while running and biking we have
x + y = 27
8.5t1 + 16t2 =27 ------(1)
t1 + t2 = 2 --------------(2)
The simultaneous equation gives us
t1 = 2/3 and t2 which is time she biked = 4/3
So 4/3 = 1 1/3. Which is 1 hour 20 minutes</span>
Answer: Expression for the amount raised by Rachel = x
Expression for the amount raised by Francesca = x+10.50
Step-by-step explanation:
Let x = the amount raised by Kayla.
Since Rachel and Kayla each raised the same amount.
then, expression for the amount raised by Rachel = x
Francesca raised $10.50 more than each of them.
Then, expression for the amount raised by Francesca = x+10.50
Answer:
5,400
Step-by-step explanation:
7c = 2t; t = 7c/2
6c +5t = 10575
6c + 5(7c/2) = 10575
6c + 35c/2 = 10575
multiply all through by 2
12c + 35c = 21,150
47c = 21,150
c = 21150/47 = 450
12 chairs = 450 × 12 = 5,400
Equation 1 = 4.12
Equation 2 = 5.099
Equation 3 = 4
Equation 4 = 3
I think the answer is B.