Math problem help pls

f(3) = 2(3)² + 4(3) - 3
=2(9) + 12 - 3
=18 + 12 - 3
=27

For the quadratic formula, if ax² + bx + c = 0, then x= [-b (+/-) √(b² - 4ac)] / 2a
So for 5m² +8m + 1 = 0, a=5, b=8, c=1.

x=[ -b (+/-) √(b² - 4ac) ] / 2a
= [-8 (+/-) √(8² - 4*5*1) ] / 2*5
= [-8 (+/-) √(64 - 20) ] / 10
= [-8 (+/-) √(44) ] / 10
= [-8 (+/-) 2√(11) ] / 10
= [-4 (+/-) √11 ] / 5

f(x) = 2x² + 4x -3
f(3)= 2*3^2 +4*3 -3
=2*9 +4*3-3
=18+12-3
=27

5m² +8m + 1 = 0
a=5,b=8,c=1

x = -8±√ [8^2 -4*5*1]/2*5
= -8±√[64-20]/10
= [ -8±√44]/10
=[-8± 2√11]/10
=2[-4±√100]/10
[-4±√11]/5

the first one is simple, just replace x by 3 f(3)=2*3² + 4*3 -3=18+12-3=27

on the second one you just have to put the number son the equation, the result will be = to (-8+√24)/10 and (-8-√24)/10

2x^2 + 4x - 3 where x = 3
= 27

5m^2 + 8m + 1 = 0
m = 1/5 (-4 - sqrt(11)) and m = 1/5 (sqrt(11) - 4)