Answer:
A book is worth $1 and a DVD is worth $12.
Step-by-step explanation:
The equations (2 unknowns and two equations, d is for a DVD and b is for a book):
For David: 3d+4b=40
For Anna: d+6b=18
Now multiply the second equation with -3 and add to the first equation:
3d+4b=40
−3d−18b=−54
Combined equation: −14b=−14 and b=1 (means that each book is worth $1).
Now for DVD price, use the second equation:
d=18−6 or d=12 (means that each DVD is worth $12).
A book is worth $1 and a DVD is worth $12.
Answer:
x = 4 ±
Step-by-step explanation:
Given
x² - 8x = 3
To complete the square
add ( half the coefficient of the x- term )² to both sides
x² + 2(- 4)x + 16 = 3 + 16
(x - 4)² = 19 ( take the square root of both sides )
x - 4 = ± ( add 4 to both sides )
x = 4 ±
Answer:
t H(t) g(t)
1 139 58.7
2 151 97.4
3 131 136.1
4 79 174.8
between 2nd and 3rd both are equal.
it shows they are at same height when t is between 2 and 3
You can use a square plus b square equal C square to fijd each length . or you can memorize the special triangles or you can also do proportional problem. it all works
complementary angles = 90 degrees
two angles would be BGC (35 degrees) and CGD ( 55 degrees)
35+55 = 90