Answer:
<u>The number of pens = 120 and the number of pencils = 200</u>
Step-by-step explanation:
Let the number of pens x, and the number of pencils is y
the cost of one pen $1, and the cost of one pencil $0.5
The cost of the whole purchase was $220
1 * x + 0.5 * y = 220
x + 0.5 y = 220 ⇒ eq.(1)
there were 80 more pencils than pens
y - x = 80 ⇒ eq.(2)
from eq.(2) x = y - 80
By substitution with x from the last equation at eq.(1)
∴ (y - 80) + 0.5 y = 220
1.5y = 220 + 80 = 300
y = 300/1.5 = 200
x = y - 80 = 200 - 80 = 120
<u>So, the number of pens = 120 and the number of pencils = 200</u>
Answer:
The standard form of a circle's equation is (x-h)² + (y-k)² = r² where (h,k) is the center and r is the radius.
Step-by-step explanation:
8x+4x-4
12x-4 is the answer
Answer:
See explanation.
(Before continuing reading, I took the base to be 3. Please tell me if you didn't want the base to be 3.)
Step-by-step explanation:
I assume 3 is suppose to be the base. Let's list some values that can be written as 3 to some integer.
3^0=1
3^1=3
3^2=9
3^3=27
3^4=81
3^5=243
......
I could have also did negative integer powers, but this is all I really need to convince you that log_3(28) is between 3 and 4.
log_3(28) means the value x such that 3^x=28.
Since 28 is between 27 and 81 in my list above, that means 3^x is between 3^3 and 3^4. This means that x is a value between 3 and 4.
Answer:
138
Step-by-step explanation:
p(x) = 3x^4 + 2x^3 − 4x^2 + 21
Let x = 2
p(2) = 3*(2)^4 + 2*(2)^3 − 4*(2)^2 + 21
= 3*16+2*8-4*4+21
=48+16-16+21
= 69
This is per girl
There are 2 girls
2 * 69
138