The correct answer would be 21.21
Answer:
5x^2 + 12x -3 =0 ---------> solve by quadratic formula
x^2 -4x = 8 ----------> solve by completing the square
4x^2 -25 = 0 ----------> solve by square root method
x^2-5x+ 6 = 0 -----------> solve by factoring
Step-by-step explanation:
1. 5x^2 + 12x -3 =0
The best way to solve this equation is quadratic formula as all the terms in the equation have coefficients it will be convenient to solve it through quadratic formula.
2. x^2 -4x = 8
The best way to solve this equation is by completing the square as the factors cannot be made directly.
3. 4x^2 -25 = 0
the best way to solve this equation is to solve by square root method as the 25 and 4 are perfect squares.
4. x^2-5x+ 6 = 0
The best way to solve this equation is to solve by factoring as it can clearly be seen that it is convenient to make factors ..
Step-by-step explanation:
Money in the beginning: 400$.
Money after the first raise: 400$+5%*400$=420$
5%*400= 5*400/100=20$
The second raise is applied on the money AFTER THE FIRST RAISE.
420$+6%*420=445.2$
6%*420= 420*6/100 = 25.2$
