Answer:
Step-by-step explanation:
I have 30 coins, all nickels, dimes, and quarters, worth $4.60. There are two more dimes than quarters. How many of each kind of coin do I have.
..
let quarters be x
dimes = x+2
...
dimes + quarters = x+x+2=2x+2
...
nickels = 30-(2x+2)
...
5(30-(2x+2))+10(x+2)+25x=460
5(30-2x-2)+10x+20+25x=460
150-10x-10+10x+20+25x=460
160+25x=460
-160
25x=460-160
25x=300
/25
x=300/25
x=12 ---- quarters
x+2= 12+2=14 dimes
30-(2x+2)=4 nickels
...
check
4*5+14*10+12*25=20+140+300=460
Answer:
68
Step-by-step explanation:
The expression is given as:
4( 3+ 7y) + 6(2 - y)
It is known that y is equal to 2. Therefore, substitute 2 in for y.
4(3+7(2))+6(2-2)
Now, solve according to PEMDAS: Parentheses, Exponents, Multiplication, Division, Addition, Subtraction
Solve inside of the parentheses first.
4(3+7(2))+6(2-2)
4(3+14)+6(0)
4(17)+6(0)
Multiply
68+0
Add
68
if you look at the part where the first part connects with the second part:
y = 5 if x < - 2
y = -2x + 1 if -2 ≤ x < 1
we don't have a discontinuity there, so there shouldn't be a dot.
<h3>
</h3><h3>
What is wrong with the graph?</h3>
When we graph over intervals like (a, b) or [a, b] or something like that, we use dots to define the end of the intervals, and to denote that the function ends abruptly or we have a jump.
In this case, you can see that between the end and the second part and the beginning of the third part there is a jump, so the use of dots is correct there, but if you look at the part where the first part connects with the second part:
y = 5 if x < - 2
y = -2x + 1 if -2 ≤ x < 1
we don't have a discontinuity there, so there shouldn't be a dot.
That is the only error with the graph.
If you want to learn more about piecewise functions:
brainly.com/question/3628123
#SPJ1
Answer:
2 a
Step-by-step explanation:
Possible derivation:
d/dx(2 a x + 2 a y)
Differentiate the sum term by term and factor out constants:
= 2 a (d/dx(x)) + d/dx(2 a y)
The derivative of x is 1:
= d/dx(2 a y) + 1 2 a
The derivative of 2 a y is zero:
= 2 a + 0
Simplify the expression:
Answer: 2 a
Step-by-step explanation:
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