Let x = the total number of pennies her piggy bank can hold.
Then 2/3x = the number of pennies she started with
Then 2/3x - 80 = the number of pennies she has left after taking out 80 pennies.
Then 1/2x = the number of pennies she has left after taking out 80 pennies.
Build the equation.
2/3x - 80 = 1/2x
Subtract 1/2x from each side of the equation.
(2/3x - 80) - 1/2x = 1/2x - 1/2x
1/6x - 80 = 0
Add 80 to both sides of the equation.
(1/6x - 80) + 80 = 0 + 80
1/6x = 80
Divide both sides by 1/6.
(1/6x) / 1/6 = 80 / 1/6
x = 480
So, Linda's piggy bank can hold 480 pennies!
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
if you would like to discover more about simultaneous equations, you can have a look at my Instagram page (learntionary). I'll be posting mathematics related stuff there and some of my notes (simultaneous enq notes are already posted!)
Answer:
Step-by-step explanation:
To find the area subtract the area of the semicircle from the area of the rectangle.
Although the line isn’t there, if you imagine there is one, then you will see that you form a rectangle which is the same line as the semicircle’s diameter.
The area of rectangle is:
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The area of the semicircle;
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*Note here that the radius is half the diameter, so it is 7cm, not 14cm
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Finally subtract the two areas;
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