Given:
Three numbers in an AP, all positive.
Sum is 21.
Sum of squares is 155.
Common difference is positive.
We do not know what x and y stand for. Will just solve for the three numbers in the AP.
Let m=middle number, then since sum=21, m=21/3=7
Let d=common difference.
Sum of squares
(7-d)^2+7^2+(7+d)^2=155
Expand left-hand side
3*7^2-2d^2=155
d^2=(155-147)/2=4
d=+2 or -2
=+2 (common difference is positive)
Therefore the three numbers of the AP are
{7-2,7,7+2}, or
{5,7,9}
7. The slope is the number with the x next to it, so it would be -6x
8. The y-Intercept is the number WITHOUT the x, in this case would be -5
9. You always want the equation to be in y = M(slope)x + b(y-intercept). Subtract 2x on both sides to get 4y = -2x + 12. Divide both sides by 4 to leave y by itself. That leaves us with y = -1/2 + 3
10. Same thing minus x on both sides to get -3y = -x + 6. And since you don’t want a negative y, you need to divide by a negative. Divide both sides by -3 to get y = 1/3 -2. When you divide a number by a negative, it changes the sign in front of the number.
Hope this helps!
477
The value of the first 7 from the left is 70.
If you divide 70 by 10, you get the value of the second seven, 7.
Another way to know this is equivalent fractions:
1/10 = 7/10
10 X 7 = 70
1 X 7 = 7
The zeros of the given functions are shown on the attached picture.
<span>No changing the map scale does not change actual distances. </span>
