To solve this, you need to isolate/get the variable "n" by itself in the equation:
Multiply 21 on both sides to get "n" by itself
Simplify the fraction
-18 = n
Answer:
Step-by-step explanation:
1) If you really meant X^2+12=40, then this simplifies to x^2 = 28, and therefore x = ±√28, or x = ±2√7.
2) If you meant X^2+12x=40:
a) Take half of the coefficient of x: that would be (1/2)(12), or 6.
b) Square this result, obtaining: 6² = 36
c) Add this 36 to x^2 + 12x + 40, and then subtract it: We get:
x² + 12x + 36 - 36 = 40, or x² + 12x + 36 = 76
We have to add 36, as indicated above, to "complete the square."
Answer:
280 ft squared
Step-by-step explanation:
To find the area of the nonshaded portion, we can find the area of the entire floor and then subtract the shaded area.
The total area is that of a rectangle: 30 * 15 = 450 ft squared.
Now, the shaded region is made up of a rectangle and a triangle.
- The rectangle has length 8 and width 10, so its area is 10 * 8 = 80 ft squared.
- The triangle has base 12 and height 15, so using the area of a triangle formula: 
(where b is the base and h is the height) = (12 * 15)/2 = 180/2 = 90 ft squared.
- The total shaded region is: 80 + 90 = 170 ft squared
Subtract 110 from 450: 450 - 170 = 280 ft squared.
Thus, the answer is 280 ft squared.
Hope this helps!
Your answer is that last one 8 3/4
Jace bought 4 cookies and 2 brownies from the bakery.
Let x represent the number of cookies and y represent the number of brownies.
Since he bought $9 worth of cookies and brownies. Each cookie costs $0.75 and each brownie costs $3. hence:
0.75x + 3y = 9 (1)
Also, he bought twice as many cookies as brownies, hence:
x = 2y
x - 2y = 0 (2)
Solving equation 1 and 2 simultaneously gives x = 4, y = 2
Hence Jace bought 4 cookies and 2 brownies from the bakery.
