Answer:
8 inch
Step-by-step explanation:
radius is half the diameter
Answer:
28 units
Step-by-step explanation:
ABCD is a rectangle. AC and BD are diagonals intersecting at point E.
Diagonals of a rectangle bisect each other.
(diagonals of a are equal in measure)
To solve this problem you must apply the following proccedure:
1. <span>You have a total of 21 coins, all nickels and dimes. Then:
x:nickels=5 cents
y: dimes=10 cents
x+y=21
2. You have that the total value is $1.70. Then:
5x+10y=170
3. The system of equation is:
x+y=21 (i)
5x+10y=170 (ii)
4. You have:
x+y=21
x=21-y
5(21-y)+10y=170
105-5y+10y=170
y=13 dimes
x+13=21
x=8 nickels</span>
Answer:
B
Step-by-step explanation:
x + 3y = 7 → (1)
3x + 2y = 0 → (2)
Multiplying (1) by - 3 and adding to (2) will eliminate x
- 3x - 9y = - 21 → (3)
Add (2) and (3) term by term to eliminate x
0 - 7y = - 21
- 7y = - 21 ( divide both sides by - 7 )
y = 3
Substitute y = 3 into either of the 2 equations and solve for x
Substituting into (1)
x + 3(3) = 7
x + 9 = 7 ( subtract 9 from both sides )
x = - 2
solution is (- 2, 3 ) → B
Somebody's starting complex numbers. One confusing thing is the principal square root of a negative number is a positive number times <em>i.</em>