The scientific mathematical language barrier.
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.
£376=117.5% so (376/117.5)= 1% x 100= £320 is the original price
Answer:
2x^2 +11
Step-by-step explanation:
f(x) = 3x^2 +2
g(x) = x^2 -9
f(x) - g(x) = 3x^2 +2 - (x^2 -9)
Distribute the minus sign
= 3x^2 +2 -x^2 +9
Combine like terms
= 2x^2 +11
