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Help please!! i don’t understand this one!

Help please!! i don’t understand this one!-example-1
User Phil Peace
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1 Answer

4 votes

Answer:

C, D

Explanation:

This equation can be solved any of several ways. One that doesn't require much thought is using the quadratic formula.

For ax² +bx +c = 0, the solutions are ...


x=(-b\pm√(b^2-4ac))/(2a)

In the given equation, a=2, b=11, c=5, so this becomes ...


x=(-11\pm√(11^2-4\cdot2\cdot5))/(2\cdot2)=(-11\pm√(81))/(4)\\\\x=(-11\pm9)/(4)=\left\{-(20)/(4),-(2)/(4)\right\}=\{-5,-(1)/(2)\}

The solutions are ...

C. x = -5

D. x = -1/2

_____

My personal favorite is using a graphing calculator. The solutions are the x-intercepts of the expression on the left. That is, where its value is zero, as the equation says.

Help please!! i don’t understand this one!-example-1
User Mrchad
by
6.4k points