Answer: 9
Step-by-step explanation:
When you multiply 9*9, you get 81 whose sum is 9 (8+1)
Likewise, 9*8=72( 7+2=9)
Answer: It’s y= 1/3x + 4
Step-by-step explanation: Because if you try to graph it then you get the points right. 4 will be on the y-axis of the chart.
Compatible numbers are numbers that are close to the numbers they're replacing that divide evenly into each other
NOTES<span><span> Compatible numbers are numbers that are close to the numbers they're replacing that divide evenly into each other</span><span> <span>When we estimate we're trying to make the problem easier, so we can solve it without doing calculationsDividing is easier when we have numbers that divide evenly into each other, so that's how we'll estimate</span></span><span> <span>56,000 is like 560 times 100800 is like 8 times 100When we divide 56,000 by 800, we can cancel out the 100's, and we're left with 560 divided by 8In other words, since there are two zeroes in the divisor, we cancel out two zeros in the dividend</span></span><span> Since we rounded the dividend and divisor into such nice numbers, we can easily divide the front digits to get a round number!</span><span> Since we canceled a few zeroes, there's only one zero left</span><span> </span><span> <span>There are usually more than just one pair of compatible numbers to choose fromAs long as the numbers are easily divisible and close to the original numbers, they'll be good compatible numbers!<span>We'll get a slightly different answer, but it's still a good estimate of our quotient</span></span></span></span>
use 
to get 
then use 
and 
also, 
to get 
then again use the first identity In both pairs, i.e.
to get 
multiply and divide by 4 to get the RHS.
because, 
squaring both sides, 
