Ask question

Ask question

All categories

3 years ago

5

Solve this quadratic equation 2x^2+x-5 = 0

1 answer:

DIA [1.3K]3 years ago

3 0

2x^2+x-5=0
+5 +5
2/2x^2+x=5/2
x^2+x=2.5
square root both sides
x+x=1.58
2/2x=1.58/2
x=0.79

You might be interested in

What is equivalent expression to 5y^-3?

docker41 [41]

Go follow my insta maddie_hinote_
Go follow nowww reeeeeeeekkk

5 0

2 years ago

Ordenar de menor a mayor estas fracciones 1/6,1/8,1/3

ludmilkaskok [199]

Order the fractions in ascending order:
{1/6,1/8,1/3}
={4/24,3/24,8/24}
=> in ascending order:
3/24,4/24,8/24
= 1/8, 1/6, 1/3

6 0

2 years ago

In a parenting magazine, Mrs. Smith read an advertisement about all the different ways that bleach can be used to kill bacteria.

babymother [125]

Question:

(a) How many bacteria would be found in 24 hours

(b) How many bacteria would be found in 2 days

(c) How long for 1000 bacteria to be found

Answer:

(a) 282429536481 bacteria

(b) $7.97*10^{22$ bacteria

(c) 6 days

Step-by-step explanation:

The question illustrates an exponential function

$y = ab^x$

Where

$a = Initial\ Value = 1$

$b=Rate = 3$ --- i.e. triples

$x = number\ of\ hours$

Solving (a): Bacteria in 24 hours

In this case:

$x = 24$

Substitute $x = 24$ , $b = 3$ and $a = 1$

So:

$y = ab^x$

$y = 1 * 3^{24$

$y = 1 * 282429536481$

$y = 282429536481$ bacteria

Solving (b): Bacteria in 2 days

$2\ days =48\ hours$

So:

$x = 48$

Substitute $x = 48$ , $b = 3$ and $a = 1$

So:

$y = ab^x$

$y = 1 * 3^{48$

$y =7.97*10^{22$ bacteria

Solving (c): How long for 1000 bacteria

In this case:

$y = 1000$

Substitute $y = 1000$ , $b = 3$ and $a = 1$

So:

$y = ab^x$

$1000 = 1 *3^x$

$1000 = 3^x$

Take Log of both sides

$Log1000 = Log3^x$

This gives:

$Log1000 = xLog3$

Make x the subject

$x = \frac{Log1000}{Log3}$

$x \approx 6$

<em>Hence: It takes 6 days</em>

8 0

2 years ago

If two angels are supplementary and one of them is 30 degrees what is the measurement for the second angle

drek231 [11]

Two angles are supplementary if they add up to 180°.

?+ 30°= 180°
⇒ ?= 180° -30°
⇒ ?= 150°

The measurement of the second angle is 150°.

6 0

2 years ago

The fox population in a certain region has a relative growth rate of 5 percent per year. It is estimated that

Wewaii [24]

Use the function from part a to estimate the fox population in the year 2006.round to the nearest fox

3 0

2 years ago