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3 years ago

What value of B makes the expression. x² + Bx + 81 a perfect square trinomial?

Mathematics

2 answers:

Lina20 [59]3 years ago

5 0

Answer:

Step-by-step explanation:

$\text{Use}\ (a+b)^2=a^2+2ab+b^2\\\\\text{We have}\ x^2+Bx+81.\\\\\underbrace{x^2+Bx+9^2}_{a^2+2ab+b^2}\to Bx=2(9)x\\\\Bx=18x\to B=18$

Oxana [17]3 years ago

4 0

Answer:

B.) 18

Step-by-step explanation:

To find the correct b value we use this formula

b² - 4ac = 0

b = What we are solving for

a = 1

c = 81

b² - 4(1)(81) = 0

b² - 324 = 0

b² = 324

$b = \sqrt{324}$

b = ±18

And 18 is one of the answer choices

So B.) 18 is the correct answer.

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HELP PLEASE <br> solve the right triangle

aleksandrvk [35]

Answer:

Part 1) $FG=4.4\ units$

Part 2) $EF=3.9\ units$

Part 3) $m\angle G=63^o$

Step-by-step explanation:

step 1

Find the measure of length side FG

In the right triangle EFG

we know that

$sin(27^o)=\frac{GE}{FG}$ ----> by SOH (opposite side divided by the hypotenuse)

substitute the given values

$sin(27^o)=\frac{2}{FG}$

$FG=\frac{2}{sin(27^o)}=4.4\ units$

step 2

Find the measure of length side EF

In the right triangle EFG

we know that

$cos(27^o)=\frac{EF}{FG}$ ----> by CAH (adjacent side divided by the hypotenuse)

substitute the given values

$cos(27^o)=\frac{EF}{4.4}$

$EF=cos(27^o)(4.4)=3.9\ units$

step 3

Find the measure of angle G

we know that

$m\angle G+27^o=90^o$ ---> by complementary angles in a right triangle

$m\angle G=90^o-27^o=63^o$

7 0

3 years ago

Which method will NOT get you to the point (4,3.5)?

lesantik [10]

Answer:

A. Starting at the origin, go 3.5 spaces to the right and then 4 spaces up.

Step-by-step explanation:

if you were to plot this then the point would be (3.5,4) instead of (4,3.5)

3 0

3 years ago

Julio caught 3 fish weighing a total of 23 1/2 pounds. One fish weighed 9 5/8 pounds and another weighed 6 1/4 pounds. How much

Airida [17]

So we need to know what 23 1/2 + 9 5/8 + 6 1/4 is.
first, we need to make them into equivalent fraction.
so...
23 1/2 can be 23 4/8
9 5/8 and
6 1/4 can be 6 2/8
let's add the whole numbers.
23 + 9 + 6 = 38
4/8 + 5/8 + 2/8 = 11/8 = 1 3/8
so 38 + 1 3/8 is 39 3/8
the answer is 39 3/8 pounds

4 0

2 years ago

Read 2 more answers

Now go to diagonals of parallelograms. You'll see two line segments, and marked with their midpoints, E and F. Verify that E and

AURORKA [14]

Answer:

AE=4

EC=4

BF=2.24

FD=2.24

Step-by-step explanation:

here we go honey

5 0

2 years ago

When 10 is subtracted from the quotient of a number divided by 4, the difference is 2. What is the number?

SOVA2 [1]

Answer: 6 I belive

Step-by-step explanation:

4 0

3 years ago