Answer: D
Step-by-step explanation:
Answer:
add 21 to both sides to get everything on one side
x^2 - 10x + 21 = 0
do factorization, guess and check
(x - 7) (x -3) = 0
x =7, and x =3
Answer:
16
Step-by-step explanation:
I dont really inderstand but i would say 16 because it is closer to adding up to 43 so yea
First you need to find the surface area of the wall that was painted, and then add the additional area in the hallway that was painted.
The wall that was painted was 9 feet by 10 feet, or 90 square feet. 90 square feet plus the additional 46 square feet in the hallway is 136 square feet, which is the total area that the paint covered.
Therefore the solution is 136 square feet.
I'm not sure if it only wants you to find Equation 1 or go further and solve:
x = the number of 5c coins
y = the number of 10c coins
Equation 1: the total number of coins is 65
x + y = 65
total value of $3.80
0.05x + 0.1y = 3.8
<u>Simultaneous Equations</u>
Make one coefficient the same
10 * (0.05x + 0.1y = 3.80 = 0.5x + y = 38
x + y = 65
0.5x + y = 38
Subtract the equations
(x + y) - (0.5x + y)= 65 - 38
(x - 0.5x) + (y - y) = 65 - 38
0.5x = 27
x = 54
Substitute it into the original equation to find y.
x + y = 65
54 + y = 56
y = 65 - 54 = 11
Substitute it into the other equation to check it's right.
0.05x + 0.1y = 3.8
0.05(54) + 0.1(65) = 3.8
x = 54 5c coins
y = 11 10c coins
