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3 years ago

The quadratic equation 2x^2 + bx + 18 = 0 has a double root. Find all possible values of b.

1 answer:

4 0

When a quadratic equation ax^2+bx+c has a double root, the discriminant,
D=b^2-4ac=0
Here
a=2,
b=b,
c=18
and
D=b^2-4ac=b^2-4*2*18=0
solve for b
b^2-144=0
=> b= &pm; sqrt(144)= &pm; 12

So in order that the given equation has double roots, the possible values of b are &pm; 12.

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A feasible region is bounded by the constraints: 20 20 4 5 0.25 y x y x y x            The objective function is P

aev [14]

I think it is C I am just guessing

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3 years ago

you flip a coin and then select one ball from a box that contains 6 balls number 1,2,3,4,5,6. how many oitcomes are in the sampl

ehidna [41]

There are 12 outcomes. The coin can land on either heads or tails, and then you can extract any number from 1 to 6 from the box. So, the outcomes are

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7 0

3 years ago

Find the perimeter of each of the two non congruent triangles where a=15,b=20 and a=29

Alborosie

Answer:

b. about 63.9 units and 41.0 units

Step-by-step explanation:

In question ∠a= 29° and Side of a= 15 and b= 20

Using sine rule of congruence of triangle.

⇒ $\frac{a}{sin A} = \frac{b}{sin B} = \frac{c}{sin C}$

⇒ $\frac{15}{Sin 29} = \frac{20}{sin B}$

Using value of sin 29°

⇒ $\frac{15}{0.49} = \frac{20}{sin B}$

Cross multiplying both side.

⇒ Sin B= $\frac{20\times 0.49}{15} = 0.65$

∴ B= 41°

Now, we have the degree for ∠B= 41°.

Next, lets find the ∠C

∵ we know the sum total of angle of triangle is 180°

∴∠A+∠B+∠C= 180°

⇒ $29+41+B= 180$

subtracting both side by 70°

∴∠C= 110°

Now, again using the sine rule to find the side of c.

$\frac{b}{SinB} = \frac{c}{SinC}$

⇒ $\frac{20}{sin41} = \frac{C}{sin110}$

Using the value of sine and cross multiplying both side.

⇒ C= $\frac{20\times 0.94}{0.65} = 28.92$

∴ Side C= 28.92.

Now, finding perimeter of angle of triangle

Perimeter of triangle= a+b+c

Perimeter of triangle= $(15+20+28.92)= 63.9$

∴ Perimeter of triangle= 63.9 units

7 0

2 years ago

Aishas mother is five times older than aisha.the sum of their ages is 30.how old is aisha?

Cloud [144]

m = 5a

m + a = 30

Because we already know the value of m, we can find the value of a.

5a + a = 30

Combine like terms.

6a = 30

Divide both sides by 6

a = 5

Now that we know the value of a, we can find the true value of m.

m = 5a

m = 5 * 5

m = 25

Aisha is 5 years old, and Aisha's mother is 25 years old. (This is your answer.)

5 0

3 years ago

This recipe makes 30 shortbread fingers.

siniylev [52]

Answer:

24 g butter

12 g sugar

36 g flour

Step-by-step explanation:

The recipe makes 30 shortbread fingers.

She wants to make 6 fingers.

6/30 = 1/5

She wants to make 1/5 of the recipe, so she needs 1/5 of each ingredient's amount.

Divide each amount by 5.

Recipe:

Makes 30 30/5 = 6 Makes 6

120 g butter 120/5 = 24 24 g butter

60 g sugar 60/5 = 12 12 g sugar

180 g flour 180/5 = 36 36 g flour

8 0

2 years ago