Sin78 ×cos42+cos78×sin42 evaluate without the use of a calculator

Answers

Answer 1

Answer: sin a * cos b + cos a * sin b=sin (a+b)

sin 78 * cos 42 + cos 78* sin 42=sin (78+42)=sin 120=sin(180-120)=
sin 60=√3 / 2

Answer: sin 78 * cos 42 + cos 78* sin 42=√3 / 2

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Can anyone help? (I'm terrible at math)

Set A(18, 12), (20, 17), (24, 10), (25, 6), (28, 4), (30, 4), (32, 2), (34, 3)
Set B
(12, 18), (17, 20), (10, 24), (6, 25), (4, 28), (4, 30), (2, 32), (3, 34)
a. Graph A, Set A
b. Graph A, Set B
c. Graph B, Set A
d. Graph B, Set B

Answers

Answer:

b graph A, set B

Step-by-step explanation:

B—> Graph A, Step B

Explanation

Solve each equation (steps as to how appreciated)

Answers

Answer:

{0}

Step-by-step explanation:

|n/6| + 1 = 1

Subtract 1 from each side

|n/6| + 1-1 = 1-1

|n/6| =0

Since this is equal to zero what is inside the absolute value must equal zero

n/6 =0

n =0

Answer:

B) {0}

Step-by-step explanation:

Let's go step by step

|n/6| + 1 = 1

First step is to subtract 1 from both sides:

|n/6| = 0

Now, we can multiply both sides by 6:

n = 0

Hope this helps :)

At what point does the graph of 5x + 4y = 12 intersect the y-axis?

Answers

first step is to simplify the equation or calculate..... so the formate of y=mx+b
4y=-5x+12
y=-5/4+3

so slope m=-5/4
b=3
count 3 on the y intercept from zero going up 3,put a dot there . then go down -5 from 3 and then count right 4 and put a dot there.if you need more help ask me or message me.

In there x=0 so 4y=12 or y=3. The point is (0,3)
That x=0 is the definition for x intersecting the axis.
We're at the same lesson now, lol.

During track practice, Britney ran 2 miles and sprinted 3,200 feet. In total, how many feet did she travel during practice?

Answers

there are 5280 feet in one mile so time 5280 by 2 than ad 3200. so your answer is 13760.

Solve for 2 unknowns
3y + 3x =24
6y+3x = 39

Answers

The two unknown variable in the two given equations are "x" and "y".
3y + 3x = 24
Dividing both sides by 3 we get
y + x = 8
x = 8 - y
Putting the value of y in the second equation we get
6y + 3x = 39
Dividing both sides by 3 we get
2y + x = 13
2y + 8 - y = 13
y = 13 - 8
= 5
Putting the value of y in the first equation we get
y + x = 8
5 + x = 8
x = 8 - 5
x = 3
So the value of x is 3 and the value of y is 5. I hope the procedure is clear enough for you to understand.

this is my answer:):):):)

School starts in 45 minutes and you live 17 miles from school. What average speed (in miles per hour) do you need to travel in order to arrive at school on time?

Answers

The required average speed to reach the school is 2.65 miles per minute.

Given that,
School starts in 45 minutes and you live 17 miles from school.
To determine at what average speed (in miles per hour) you need to travel in order to arrive at school on time.

What is speed?

Speed is defined as when an object is subjected to move, the distance covered by the object in a certain time interval is the speed of that object.

What is average?

The average of the values is the ratio of the total sum of values to the number of values.

Here,
Distance = 17 miles
Time = 45 minutes

Speed = distance / time
Speed = 45 / 17
Speed = 2.65 miles per minute

Thus, the required average speed to reach the school is 2.65 miles per minute.

Learn more about average here:

brainly.com/question/24057012

#SPJ2

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