Help
Options
Didn't know it?
click below
click below
Knew it?
click below
click below
Don't Know
Remaining cards (0)
Know
retry
shuffle
restart
0:00
Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.
Normal Size Small Size show me how
Normal Size Small Size show me how
Module_17
Solving Equations by the Quadratic Formula and Quadratic Methods
| Question | Answer |
|---|---|
| Use the quadratic formula to solve this equation. d^2 + 7d -8 = 0 | Since the eqaution is in standard form, substitute values of a, b, and c into the quadratic fthe ormula. Thus, d= (-(1) +/- sqaure root ((7^2) - 4(1)(-8))/ 2(1). Multiply. Then, simplify the sqaure root to get the solutions d= -8 and 1. |
| Use the quadratic formula to solve this equation. 1/2x^2 + 5x -1 = 0 | Clear the equation of fractions by multiplying both sides of the equation by the LCD 2. Substitute the values of a, b, and c into the quadratic formula and solve. The solutions for x are -5 +/- 3* the sq.rt. of 3. |
| Solve. p^4 - 1296 = 0 | Factor the binomial into two binomials since this equation is the difference of two squares. Thus, the equation becomes (p^2 - 36)(p^2 + 36) = 0. Set each factor to 0 and solve for p. The solutions are 6, -6, 6i, -6i. |
| Solve. x^2/3 - 2x^1/3 - 15 = 0 | Substitute the variable u in the original equation for x^1/3. The equation becomes u^2 - 2u - 15 = 0. Solve for u by factoring the equation. Thus, u = 5 or u = -3. Since x^2/3 = (x^1/3)^2, substitute x^1/3 back in for the variable u. x = 125, x = -27 |
| Solve. (2n + 1)^2 + 7(2n + 1) - 8 = 0 | Substitute variable y in where there is a (2n+1) since it is repeated. The equation becomes y^2+7y-8=0. Factor the equation (y+8)(y-1)=0. Set each factor to 0. Solve for y. y= -8 or 1. Sub in (2n+1) back for the variable y and solve for n. n= -9/2 and 0 |
| Find all real and complex roots. x^4 - 19x^2 + 48 = 0 | First, sub in a linear term for the variable raised to the lowest power. Let y=x^2; y^2=x^4. The new equation is y^2-19y+48=0. Factor. (y-16)(y-3)=0. Set factors to 0. y=16 or 3. Sub x^2 back for variable y to find the original value, x. x=+/-4; +/- sqrt3 |
| Solve. y^3 + 25y -3y^2 - 75 = 0 | Factor by grouping. Group so that each group has a common factor. (y^3+25y)-(3y^2-75)=0. Factor out the GCF from each group. y(y^2+25)-3(y^2+25)=0. Factor out common factor (y^2+25). (y-3)(y^2+25)=0. Set factors to 0. Solve for y. Solutions are y=3; +/-5i |
Created by:
a0644929
Popular Math sets