Answer:
(a) 9, 8, 7, 6, 5, ...
Explanation:
The solution to the inequality can be done a couple of ways. The solution is similar to that for a one-step linear equation.
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reverse inequality
We know that multiplying numbers by a negative value reverses their order. For example, 1 < 2, but -1 > -2. That is, multiplying by -1 requires a change in the comparison operator if it is to remain true.
For our inequality, we want to solve it by multiplying both sides by -1/4:
-4y > -40
(-1/4)(-4y) < (-1/4)(-40) . . . . . multiply both sides by -1/4 (reverses order)
y < 10 . . . . . . . . . . . simplify
The first few decreasing integer values that are part of this solution are ...
{9, 8, 7, 6, 5, ...}
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make coefficients positive
We can add 4y+40 to both sides of the inequality. The result will be an inequality with positive coefficients. This can be solved in one step.
-4y > -40 . . . . . given
(-4y) +(4y +40) > (-40) +(4y +40) . . . . . . add 4y+40 to both sides
40 > 4y . . . . . . . . . . . . . . . simplify
10 > y . . . . . . . . . . . . divide by 10 (order is unchanged)
y < 10 . . . . . . . . . rearrange to put y on the left
Integer solutions to this inequality are ...
{9, 8, 7, 6, 5, ...}