All categories

2 years ago

Find the value of expression the a3−3a2+5a−7 by substituting a=3.

Mathematics

1 answer:

8090 [49]2 years ago

6 0

Answer:

21 is answer

Step-by-step explanation:

Find the value of expression the a3−3a2+5a−7 by substituting a=3.

You might be interested in

Need help with this question -9×3-4^2/ 3^2 + 2^2

Vesnalui [34]

-9 × 3 - 4² = -27 - 16 = -43

3² + 2² = 9 + 4 = 13

(-9 × 3 - 4²)/(3² + 2²) = -43/13 = -3 4/13

3 0

2 years ago

Solve x^2 +14x=15 by completing the square

ivanzaharov [21]

Answer:

x = -15 and x = 1

Step-by-step explanation:

Since we have to use the complete the square method, we first need to rewrite the equation in the form $x^{2}+2ax+a^{2}=(x+a)^{2}$ .

This results in $x^{2} + 14x + 7^{2} = 15 + 7^{2}$ .

Next, we simplify the equation to get $x^{2} +14x+7^{2} = 64$ .

Factoring the left side gives us $(x+7)^{2} = 64$ .

Finally we solve the equations: $x+7=\sqrt{64}$ and $x+7=-\sqrt{64}$ .

This gives us x=1, and x=-15

6 0

2 years ago

Read 2 more answers

Amira is painting a rectangular banner 2 1/4 yards wide in the cafeteria. The banner will have a blue background. Amira has enou

elena55 [62]

Area of a rectangle:
A = w x h, where w is the width and h is the height.
w = 2.25 yd
A = 1.5 yd²
1.5 = 2.25 · h
h = 1.5 : 2.25 = 0.6667 = 2/3 yd
Answer:
The height of a banner is 2/3 yard.

4 0

2 years ago

Read 2 more answers

Solve the inequality n+3<-7

Aliun [14]

Answer:

Step-by-step explanation:

n<-7-3

n<-10

=> n= (-infinitive ; -10)

5 0

1 year ago

Chase baked 4/5 dozen brownies in 3 hours ? What is her average of baking per hour ?

loris [4]

Answer:

$3\frac{1}{5}$ brownies per hour

Step-by-step explanation:

Given parameters:

Number of brownies = $\frac{4}{5}$ of a dozen

Time taken = 3hrs

Unknown:

Average baking per hour = ?

Solution:

The average baking per hour;

This is a rate problem;

Average baking per hour = $\frac{number of baking}{time}$

Number of brownies = $\frac{4}{5}$ x 12 = $\frac{48}{5}$

Average baking per hour = $\frac{48}{\frac{5}{3} }$

= $\frac{48}{5} x \frac{1}{3}$

= $\frac{16}{5}$

= 3 $\frac{1}{5}$ brownies per hour

8 0

2 years ago