Three times a number is four greater than the sum of the number and six

Can (3,5 and square root 34) be sides on a right triangle?

Two blends of tea are mixed to make a blend that will be sold at the fair. black tea sells for $2.20 per pound and orange pekoe tea sells for $3.00 per pound. how much of each should be used to obtain a 4lb blend selling for $2.50 per pound?

If f(x)=-x^2+6x-1 and g(x)=3x^2-4x-1,find(f+g)(x)