1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
wel
3 years ago
13

Solve 2x^2+9x-7=0 Give your solutions correct to 3 significant figures.

Mathematics
1 answer:
inessss [21]3 years ago
7 0

Answer:

X = -1 or X = -3.5

Step-by-step explanation:

2x^2 + 9x + 7 = 0

ac = 14

b = 9

find a two numbers which when you multiply you get 14 and add you get 9.

so it will 2 and 7. (they replace b which is 9x)

therefore: 2x^2 + 2x + 7x + 7 = 0

find common factors using each 2 from the four.

2x( x + 1) + 7 (x+1) = 0

so it will be (2x + 7) (x+1) = 0

find x,

i) 2x +7 = 0

x= -3.5

ii) x + 1 = 0

x = -1

You might be interested in
A dot plot titled hours of practice this week going from 0 to 4. 0 has 1 dot, 1 has 2 dots, 2 has 0 dots, 3 has 4 dots, and 4 ha
WITCHER [35]

Answer:

1, 2, 3, 5

Step-by-step explanation:

I took the quiz

4 0
4 years ago
Using the 10% value to find 20% of 300
neonofarm [45]
20% * 300 = 2 * (10% * 300) = 2*30 = 60
3 0
3 years ago
A firm has a fixed cost of $500 in its first year of operation. When the firm produces 100 units of output, its total costs are
HACTEHA [7]

Answer:

option (a) $250

Step-by-step explanation:

Data provided in the question:

Fixed cost = $500

For 100 units produced Total cost = $3,500

For 101 units produced, Total cost = $3,750

Now,

Marginal cost is calculated as:

Marginal cost = \frac{\textup{Total change in cost of producing more goods}}{\textup{Total change in produced goods}}

thus,

Marginal cost = \frac{\textup{Total cost of 101 units - Total cost of 100 units}}{\textup{101-100}}

or

Marginal cost = \frac{\textup{3,750-3,500}}{\textup{1}}

or

Marginal cost = $250

Hence,

The correct answer is option (a) $250

7 0
3 years ago
Reggie has a rectangular piece of paper that is 12 inches long and 7 inches wide. He is going to cut the paper from corner to co
neonofarm [45]

A property from geometry states that rectangles have congruent opposite sides. Thus, no matter which diagonal Reggie cuts, it still has the same lengths. Since it's a rectangle and we cut from corner to corner, we create a right triangle. See the picture below:

<u>___________12 inches_______</u>

7 |

i |

n |

Because it's a rectangle, it won't matter which corner we cut. But if we fold at the cut lines, we would make an in the rectangle's center.

The cut line and two sides make a right triangle. One leg is 12, one leg is 7, and we need to find the third side. The Pythagorean Theorem - sum of the squares of the legs equals the square of the hypotenuse - is applied.

Let S = the length of the side from corner to corner

S² = 12² + 7²

S² = 144 + 49

S² = 193

S = √193 or -√193

Because we are dealing with lengths, we only want positive numbers. -√193 is not used. Thus S = √193

S = √193 = 13.8924439894

S = 18.92 (rounded to two places)


Thus, Reggie will cut 18.92 inches of paper.

5 0
3 years ago
4 = -8Z - 7 + 8z<br> Giving the brainliest to whoever gets the right answer.
liubo4ka [24]

Answer:

No Solution

Step-by-step explanation:

if one side is 4, another side -8z and +8z cancels, left -7

4 ≠ -7

8 0
3 years ago
Read 2 more answers
Other questions:
  • Two dice are rolled; the numbers add to 11.
    12·1 answer
  • james' daily wage was $5 more than Davis's. Although James worked 3 days less than David, they earned $180 each. Find the number
    7·1 answer
  • Why might you expect most absolute value equations to have two solutions? Why not three or four?
    10·1 answer
  • What area formula does a triangle have?
    13·2 answers
  • naomi has earned $54 mowing lawns the past two days. she worked 2 1/2 hours yesterday and 4 1/4 hours today. if naomi is pains t
    9·1 answer
  • NEED HELP ASAP
    7·1 answer
  • Give me your best <br><br> the brainleist one can have my insta
    13·1 answer
  • The submarine is 217 feet below sea level. Identify the integer
    14·1 answer
  • Simplify each of the expression (x-7)(x+3)
    6·1 answer
  • Here is a polygon. draw a scaled copy of the polycon with scale factor 3
    5·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!