Let n = number of records.
Each record costs $7, so n records cost 7n.
She then spent $3, so the total spent is 3n + 3.
She spent a total of $24, so 3n + 3 must equal 24. That gives us the following equation.
7n + 3 = 24
Subtract 3 from both sides.
7n = 21
Divide both sides by 7.
n = 3
Answer: She bought 3 records.
It's dependent on the context. A book may ask you to find the f'(x) of a function and you may have to use a u sub in your problem which requires you to find the dy/dx of what you substitute. So in this case both would be used.
Answer:191/94 i hope this helps!!(✿◠‿◠)
Answer:
x intercepts -sqrt(5), + sqrt(5)
y intercept -5
Step-by-step explanation:
y = x^2 -5
to find the x intercept set y=0 and solve for x
0 = x^2-5
add 5 to each side
5 = x^2
take the square root of each side
+- sqrt(5) = sqrt(x^2)
x = +-sqrt(5) there are 2 x intercepts since it is a quadratic
to find the y intercept set x=0 and solve for y
y = 0-5
y = -5
Answer:
8 rabbits
22 chickens
Step-by-step explanation:
c = chickens
r = rabbits
heads - c + r = 30
legs - 2c + 4r = 76
We can now use these two equations to create one by isolating the variable (c) in the first equation.
c = 30 - r
2c + 4r = 76
2(30 - r) + 4r = 76
60 - 2r + 4r = 76
2r = 16
r = 8
Now we know that there are 8 rabbits, which means that there has to be 22 chickens in order to have 30 heads.
