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>
Divide the perimeter by 2, this will give you the sum of one length and one width.
68/2 = 34 yards
Now the length is 10 yards more, so subtract 10 from the 34 and divide by 2 again:
34 - 10 = 24
24 /2 = 12
The width is 12 yards.
The length is 12 + 10 = 22 yards.
Answer:
Step-by-step explanation:
5
3 _
18
Answer:
Step-by-step explanation:
Rewrite this quadratic equation in standard form: 2n^2 + 3n + 54 = 0. Identify the coefficients of the n terms: they are 2, 3, 54.
Find the discriminant b^2 - 4ac: It is 3^2 - 4(2)(54), or -423. The negative sign tells us that this quadratic has two unequal, complex roots, which are:
-(3) ± i√423 -3 ± i√423
n = ------------------- = ------------------
2(2) 4
Answer:
(-6,3)
Step-by-step explanation:
