Answer:
17 nickles !
Step-by-step explanation:
First, identify the variables:
n = amount of nickels
d = amount of dimes
Next, setup the equations based on what you know. The first equation is:
n + d = 28
For the second equation, we know that a dime is worth 10¢ and a nickel is 5¢, so it should be:
0.05n + 0.10d = 1.95
This a three-step answer:
In one formula (you can use any of them; most people use the simplest one), single out the variable on one side
Apply the first formula into the second formula, and solve it to get the value of one variable
Apply the answer from the second formula into the first formula, and solve it to get the value of the other variable
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Step One:
n + d = 28
n + d - d = 28 - d
n = 28 - d
Step Two:
0.05n + 0.10d = 1.95
(0.05 * (28 - d)) + 0.10d = 1.95
1.40 - 0.05d + 0.10d = 1.95
1.40 + 0.05d = 1.95
1.40 - 1.40 + 0.05d = 1.95 - 1.40
0.05d = 0.55
d = 11
Step Three:
n = 28 - d
n = 28 - 11
n = 17
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Your answer should be 17 nickels and 11 dimes.
You can double check by applying the variables into both formulas.
n + d = 28
17 + 11 = 28
28 = 28
0.05n + 0.10d = 1.95
(0.05 * 17) + (0.10 * 11) = 1.95
0.85 + 1.10 = 1.95
1.95 = 1.95
I hope this helped.
y = ( x + 9 )^2 - 2
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That is when h=0
so assuming yo meant
h(t)=-16t²+24t+16
solve for t such that h(t)=0
because when height=0, the gymnast hits the ground
so
0=-16t²+24t+16
using math (imma complete the square
0=-16(t²-3/2t)+16
0=-16(t²-3/2t+9/16-9/16)+16
0=-16((t-3/4)²-9/16)+16
0=-16(t-3/4)²+9+16
0=-16(t-3/4)²+25
-25=-16(t-3/4)²
25/16=(t-3/4)²
sqrt both sides
+/-5/4=t-3/4
3/4+/-5/4=t
if we do plus (because minus would give us negative height)
8/4=t
2=t
it takes 2 seconds
1) Let's write out both expressions subtracting 4m²+2mn+8n² from 2m²+6mn+2n²
2) Note that when we subtract 4m^2 + 2mn + 8n^2 from 2m^2 + 6mn + 2n^2 we need to swap the sign by placing -1 outside the parentheses and then combine like terms adding those terms algebraically.
