- Thread starter M.Adia
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Here, the inequality is \(\displaystyle (5- x)(1- 2x)\ge 0\) so either

1) \(\displaystyle 5- x\ge 0\)

2) \(\displaystyle 5- x\le 0\)

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The best way to solve this is through graphing the function y =(5+x)(1-2x)Hi, I have a question I'm stuck on:

(5+x)(1-2x) ≥0

I'm lost on how to solve that.

The domain of the solution would be obvious.

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Yes, a picture is worth a thousand math steps!The best way to solve this is through graphing ...

Yet another way is to use knowledge of parabolas, the vertex formula, sign of leading coefficient, and the roots of the polynomial, and put it all together to reason out the solution.

For example, if you determine that the vertex of some parabola belonging to a function h lies below the x-axis, and you see that the leading coefficient is negative, then no part of the parabola lies above the x-axis. In other words, for that particular example, h(x) is never greater than or equal to zero.

But, for students lacking a lot of practice, this approach would be more difficult than graphing.