# Equation

Equation

has one root x

b =

x

(adsbygoogle = window.adsbygoogle || []).push({});

has one root x

_{1}= 10. Determine the coefficient b and the second root x_{2}.**Result****1.6**

x

_{2}=

**-8.4**

#### Solution:

$$ \smash{ b=-(-1 \cdot 10 \cdot 10+84)/10 = \frac{ 8}{5 } = 1.6 \\~\\-x^2 +1.6x +84 =0 \\~\\x^2 -1.6x -84 =0 \\~\\D = 1.6^2 - 4\cdot 1 \cdot (-84) = 338.56 \\~\\D>0 \\~\\ \\~\\x_{1,2} = \frac{ 1.6 \pm \sqrt{ 1.6^2 - 4\cdot 1 \cdot (-84)} }{ 2 \cdot 1 } = \frac{ 1.6 \pm \sqrt{ 338.56 } }{ 2 } \\~\\x_{1,2} = 0.8 \pm 9.2 \\~\\x_{1} = 10 \\~\\x_{2} = -8.4 \\~\\ \\~\\ (x -10) (x +8.4) = 0 } $$

**Leave us a comment of example and its solution (i.e. if it is still somewhat unclear...):**

**Showing 0 comments:**

**Be the first to comment!**

#### To solve this example are needed these knowledge from mathematics:

## Next similar examples:

- Roots

Determine the quadratic equation absolute coefficient q, that the equation has a real double root and the root x calculate: ? - Quadratic equation

Solve quadratic equation: x^{2}+16x-225=0 - Variations 4/2

Determine the number of items when the count of variations of fourth class without repeating is 552 times larger than the count of variations of second class without repetition. - Quadratic equation

Quadratic equation ? has roots x_{1}= -47 and x_{2}= -79. Calculate the coefficients b and c. - Discriminant

Determine the discriminant of the equation: ? - Combinations

How many elements can form six times more combinations fourth class than combination of the second class? - 2nd class combinations

From how many elements you can create 1081 combinations of the second class? - Combinations

From how many elements we can create 990 combinations 2nd class without repeating? - Quadratic function 2

Which of the points belong function f:y= 2x^{2}- 3x + 1 : A(-2, 15) B (3,10) C (1,4) - Tubes

Iron tubes in the warehouse are stored in layers so that each tube top layer fit into the gaps of the lower layer. How many layers are needed to deposit 56 tubes if top layer has 5 tubes? How many tubes are in bottom layer of tubes? - Quadratic inequation

If 5x + x² > 100, then x is not - Equation with abs value

How many solutions has the equation ? in the real numbers? - Variation equation

Solve combinatorics equation: V(2, x+8)=72 - AS sequence

In an arithmetic sequence is given the difference d = -2 and a_{78}= 518. a) Determine the value of a_{67}b) Determine the sum of 78 members. - Seats

Seats in the sport hall are organized so that each subsequent row has five more seats. First has 10 seats. How many seats are: a) in the eighth row b) in the eighteenth row