All categories

3 years ago

7n+2 = 4n+17 solve the equation

Mathematics

1 answer:

lions [1.4K]3 years ago

5 0

Answer:

n = -5

Step-by-step explanation:

Solve for n:

n + 2 = 4 n + 17

Hint: | Move terms with n to the left hand side.

Subtract 4 n from both sides:

(n - 4 n) + 2 = (4 n - 4 n) + 17

Hint: | Combine like terms in n - 4 n.

n - 4 n = -3 n:

-3 n + 2 = (4 n - 4 n) + 17

Hint: | Look for the difference of two identical terms.

4 n - 4 n = 0:

2 - 3 n = 17

Hint: | Isolate terms with n to the left hand side.

Subtract 2 from both sides:

(2 - 2) - 3 n = 17 - 2

Hint: | Look for the difference of two identical terms.

2 - 2 = 0:

-3 n = 17 - 2

Hint: | Evaluate 17 - 2.

17 - 2 = 15:

-3 n = 15

Hint: | Divide both sides by a constant to simplify the equation.

Divide both sides of -3 n = 15 by -3:

(-3 n)/(-3) = 15/(-3)

Hint: | Any nonzero number divided by itself is one.

(-3)/(-3) = 1:

n = 15/(-3)

Hint: | Reduce 15/(-3) to lowest terms. Start by finding the GCD of 15 and -3.

The gcd of 15 and -3 is 3, so 15/(-3) = (3×5)/(3 (-1)) = 3/3×5/(-1) = 5/(-1):

n = 5/(-1)

Hint: | Simplify the sign of 5/(-1).

Multiply numerator and denominator of 5/(-1) by -1:

Answer: n = -5

You might be interested in

Double the sum of 13 and a number

Alla [95]

The answer is: 2(13+x)

6 0

4 years ago

Before a bag of flour can be sold, it must be 40 kilograms but can be within 0.5

Serjik [45]

Answer:

The minimum acceptable weight of the flour bag is 39.5 kg,

and its maximum acceptable weight is 40.5 kg

Step-by-step explanation:

Notice that the selling weight of the bag to be sold (x) needs to differ from 40 kg at most 0.5 kg. Therefore, we can write the following inequality:

$|x-40|\leq 0.5$

The inequality can be solve once we remove the absolute value symbol, and solve for the unknown "x". Recall that in order to solve it, we need to consider the two possible cases:

a) that the expression within the absolute value symbol is larger than or equal to zero, and b) that the expression is less than zero.

a) If $x-40\geq 0$ then its absolute value is equal to itself (x-40), and when we remove the absolute value symbols, we get:

$x-40\leq 0.5\\x\leq 0.5+40\\x\leq 40.5\,\,kg$

which means that the weigh "x" of the flour bag should be smaller or equal than 40.5 kg

b) If $x-40$ , then the absolute value of this is its opposite : -x+40, and the inequality becomes:

$-x+40\leq 0.5\\40\leq 0.5+x\\40-0.5\leq x\\39.5\leq x$

which means that the weight of the flour bag must be larger than or equal to 39.5 kg

So, the minimum acceptable weight of the flour bag is 39.5 kg, and the maximum acceptable weight is 40.5 kg

6 0

3 years ago

157,130,000 in scientific notation

Sindrei [870]

Step-by-step explanation:

157,130,000

=1.5713 × 10⁸

8 0

3 years ago

A car travels 32 km due north and then 46 km in a direction 40° west of north. Find the direction of the car's resultant vector.

tatuchka [14]

Answer:

Step-by-step explanation:

This requires some serious work before we even begin. First off, we will convert the km to meters:

32 km = .032 m

46 km = .046 m

And then we have to deal with the angle given as 40 degrees west of north. An angle 40 degrees west of north "starts" at the north end of the compass and moves towards the west (towards the left in a counterclockwise manner) 40 degrees. That means that the angle that is made with the negative x axis is a 50 degree angle. BUT the way angles are measured in standard form are from the positive x-axis, therefore:

40 degrees west of north = 50 degrees with the negative x axis = 130 degrees with the positive x axis. 130 is the angle measure we use. Phew! Now we're ready to start. Adding vectors requires us to use the x and y components of vectors in order to add them.

$A_x=.032cos90.0$ so