How do u do this problems 8x - 2 = -9 + 7x

The triangles are similar. what is the value of x? x=

Abike shop sells you a bicycle for $63 and a helmet for $21. the total cost is 150% of what the shop spent originally. how much did the shop spend originally? how much profit did the bike shop earn by selling the bicycle and helmet to you ?

Evaluate the discriminant of each equation. tell how many solutions each equation has and whether the solutions are real or imaginary. x^2 + 4x + 5 = 0