Answer:
f(2) = -2
Step-by-step explanation:
To solve this, you have to plug in 2 for x
f(2) = -2^2 + 2(2) - 10
= 4 + 4 - 10
= 8 - 10
= -2
Answer:
19
Step-by-step explanation:
To find 20% of 95 multiply 95 by 0.20, p5 x 0.20=19
D=dimes
n=niclkes
p=pennies
q=quarters
1 dollar (100 cents)
2 times as many nickles as dimes
n=2d
14 more pennies than quarters
p+14=q
and total is 1 dollar so
25q+10d+5n+p=100
ok so we must use logic
the max number of quarters in a dolar is 4
but there are pennies so max is 3
so q=1,2, or 3
therefor p=15,16 or, 17
also, the rest of te coins are only multipules of 5 so the sum amount of pennies and quartes must add to a multiplule of 5
if q=1 and p=15, total is 40 cents
if q=2 and p=16, total is 66 cents
if q=3 and p=17, total is 92 cents
only 40 cents is a multiplule of 10
1 quarter and 15 pennies
now we are having
40 cents is pennies and quartesrs
therfor 100-40=60 cents is nickles and dimes
60=5n+10d
n=2d
sub
60=5(2d)+10d
60=10d+10d
60=20d
divide both sides by 20
3=d
sub
n=2d
n=2(3)
n=6
6 nickles
3 dimes
answer is
1 quarter
3 dimes
6 nickles
15 pennies
<h3>Answer:</h3>
87.5 ounces
<h3>Explanation:</h3>
There's a cute "X-diagram" tool that can be used for solving mixture problems of all kinds. (See the attachment.) The numbers on the left represent the percentages of the constituents of the mix. The number in the center is the desired percentage in the resultant mix. The numbers on the right in the X are the differences along the diagonals. (6-5=1, 5-3=2)
These are also the proportions of the constituents in the final mix. That is, there are 2 parts of spice that is 6% salt for each 1 part of spice that is 3% salt. So, we need half as much of the latter as the former.
Half of 175 ounces is 87.5 ounces, the amount of 3% spice that is needed.
_____
If you really want to write an equation, you can let x represent the amount of 3% spice needed. Then the amount of salt in the mix is ...
... 175×6% +x×3% = (175+x)×5%
Dropping the percent symbols and eliminating parentheses, we have
... 1050 +3x = 875 +5x
... (1050 -875) = (5x -3x) . . . . . add -875-2x
... 175/2 = x = 87.5 . . . . . . . . . . divide by the coefficient of x