How do you solve 4b^2+2=326?

2 Answers
Jim G.
Mar 16, 2018

b=+-9

Explanation:

"subtract 2 from both sides of the equation"

rArr4b^2=324

"divide both sides by 4"

rArrb^2=81

color(blue)"take the square root of both sides"

rArrb=+-sqrt81larrcolor(blue)"note plus or minus"

rArrb=+-9

Brandon
Mar 16, 2018

b=pm9

Explanation:

As with any equation, we want to get the unknown value we are trying to work out on its own. Therefore we need to get rid of the +2, and by doing this we do the opposite to both sides, which is to -2:

4b^2+2=326 -> 4b^2=324

As we would like to have B on its own, we need to get rid of the 4 in front, and by doing this we do the opposite to both sides, which is to /4

4b^2=324 -> b^2=81

Now we want b on its own again, we do not want the ^2 added on, therefore, we do the opposite which is to sqrt:

b^2=81 -> b=pmsqrt81

-> b=pm9

Always remember the pm, and this is our final answer as it cannot be simplified further.

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