Step-by-step explanation:
the area of a circle (all 360°) is
pi×r²
with r being the radius.
the area of a circle segment is just the corresponding fraction of the whole circle.
so the area of a segment of x degrees is
pi×r² × x/360
in our case we know
pi×42240² × x/360 = 180 mi²
we also know that there are 5280 ft in 1 mile.
so, the radius is actually
42240 / 5280 = 8 miles
and therefore our equation resulting in mi² has to use miles and not ft and has to look that way :
pi×8² × x/360 = 180 mi²
pi×64 × x/360 = 180
pi×64 × x = 180×360
pi×x = 180×360/64 = 1012.5
x = 1012.5/pi = 322.2887598...°
so, the angle of the segment of a circle with the area of 180 mi² and the radius of 8 mi is 322.2887598...°
The value of a is 70° and b is 20°
So, a line parallel to <span>y - 5x = 10, will have the same slope as that equation, so what is that slope anyway? let's solve for "y".
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alrite, so the slope is 5 then, well, then the parallel line will have the same slope.
so, we're really looking for the equation of a line whose slope is 5 and runs through 3,10.
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Answer:
60 ml of 40% saline and 90 ml of 15% saline
Step-by-step explanation:
We can call the amount of 40% solution x and the amount of 15% solution y.
x + y = 150 -- (1)
0.40x + 0.15y = 150 * 0.25 -- (2) --- 150 * 0.25 = 37.5
40x + 15y = 3750 (Multiply (2) by 100 to get rid of decimals)
15x + 15y = 2250 -- (3) (Multiply (1) by 15)
25x = 1500 (Subtract (3) from (1)
x = 60
y = 150 - 60 = 90
Answer:
$69 is the total cost of the bill
Step-by-step explanation:
60(1.15)
60 is the cost of the bill, and the 1.15 is the added tax plus the previous $60.
Put 60(1.15) into a calculator and
$69