324 = a2
i need it for homework

342 = a²

switch sides:

for x² = f(a) the solutions are x = √ f(a)   and - √ f(a)

therefore:

√ 342 = 18

-√ 342 = - 18

a = 18  and a = - 18

hope this helps!

You didn't specify the topic so I will solve it in 3 topics
solving for a, you take roots of both sides and solve a=18,-18
using the quadratic formula, solve the equation for aa by finding aa, bb, and ccof the quadratic then applying the quadratic formula.

a=±√321a=±321

a≈17.91647286,−17.91647286

for factoring, Factor and set each factor equal to zero.

a=√321,−√321a=321,-⁢321

a≈17.91647286,−17.91647286