Answer:
s = 6, r = 8 or s = 4, r = 7
Step-by-step explanation:
2r - s = 10
2r = 10 + s
r = 5 + s/2 --(1)
rs - s^2 = 12 --(2)
sub (1) into (2):
(5 + s/2)s - s^2 = 12
5s + 0.5s^2 - s^2 = 12
-0.5s^2 + 5s - 12 = 0
s^2 - 10s + 24 = 0
(s - 6)(s - 4) = 0
therefore s = 6 or s = 4
when s = 6, r = 8 and when s = 4, r = 7
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Answer:
1560 in^2
Step-by-step explanation:
10x22 = 220 bottom rectangle
1/2(10)(24) = 120 side triangle
22x26 = 572 front rectangle
24x22 = 528 back rectangle
220+120+120-572+528= 1560
ANSWER
Find out the how much fluid should be drained and replaced with pure antifreeze so that the new mixture is 60% antifreeze .
To proof
let us assume that the fluid should be drained and replaced with pure antifreeze be x .
As given
A radiator contains 10 quarts of fluid, 30% of which is antifreeze.
Now write 30% in the decimal form

Now write 60% in the decimal form

After drained and replaced the fluid with pure antifreeze than the quantity becomes = ( 10 - x )
The quantity of antifreeze is

The fluid should be drained and replaced with pure antifreeze so that the new mixture is 60% antifreeze .
than the equation becomes

solyving
100x +300 - 30x = 600
70x = 300

x = 4.28 quarts (approx)
Hence 4.28 quarts (approx) fluid should be drained and replaced with pure antifreeze so that the new mixture is 60% antifreeze .
Therefore the option (c.) is correct .