recall in a perfect square trinomial, the middle term is the tale-tell guy, we know the middle term is the product of 2 and the two other guys without the exponent, so in this case 6x = 2*√x² * √c.

Possible number combinations are 1,1 2,1 3,1 4,1 5,1 6,1 1,2 2,2 3,2 4,2 5,2 6,2 1,3 2,3 3,3 4,3 5,3 6,3 1,4 2,4 3,4 4,4 5,4 6,4 1,5 2,5 3,5 4,5 5,5 6,5 1,6 2,6 3,6 4,6 5,6 and 6,6. of those 36 number combinations the ones that add up to more than 10 include: 4,6 5,5 5,6 6,4 6,5 6,6. thats 6 number combinations. 6/36 of the possible sums of the top faces equal out to 10 or more. 6/36=1/6=0.166666666666666666666666(repeating) and to put that in a percentage, 16.7%
the probability is 16.7%
Hope this helps.
Maria = x
Tom = y
Use substitution
x+y=30
2y=x
2y+y=30
3y=30
y=10
Tom is 10 years old.
x+y=30
x+10=30
x=20
Maria is 20 years old.
Plug in -6 for a and -5 for b
3(-6)^2 - 4(-5)
3(36)+20
108+20
=120