five buses can transport 130 people. how many buses are needed to transport 780 pupils?
4x^2+6x+1=0
what number compared to 21 is the same as 35 compared to 7
2x^2-7x-5=0
1470 = 0.1 × 4200 × (T-310) solve for T
\sqrt{2y^2-5y}-\sqrt{21-6y}=0
2×-3y×4y
2×-3
54/x +63/x+6 = 3
f(x-2)= x^3 then f(x) =
0.01x^2+1.2x-212.5=0
