The answer to your question is b
Answer:
D. 1800
Step-by-step explanation:
An overestimate is pretty self-explanatory, an amount bigger than what it's supposed to be.
Multiplying 22 * 68
1496
Rounding it will give you 1500, but the overestimate would be 1800. Because its a respected amount that is close to the answer of 22 * 68.
-4x+y= -9 can be turned into
y= -9 + 4x
5x+2y=3 (plug y in)
5x+2(-9+4x)=3
5x-18+8x=3
5x+8x=3+18
13x=21
divide 13 on both sides
x=1.6
0.71 x 22 is the expression that works, because 1 AUD = 0.71USD.