Ask question

Ask question

All categories

mr Goodwill [35]

3 years ago

12

What is the missing angle 78+31+x=180

1 answer:

icang [17]3 years ago

8 0

Answer:

71

Step-by-step explanation:

78+31=109 so 180-109=71

You might be interested in

Calculate the arithmetic sequence in which a9=17 and the common difference is d=-2.1

jek_recluse [69]

Answer:

$S_{31}=71.3$

Step-by-step explanation:

The nth term of an arithmetic sequence is given by the formula,

$U_n=a_1+(n-1)d$

We were given that the 9th term is $17$ .

$\Rightarrow 17=a_1+(9-1)(-2.1)$

$\Rightarrow 17=a_1+(8)\times(-2.1)$

$\Rightarrow 17=a_1-\frac{84}{5}$

$\Rightarrow 17+\frac{84}{5}=a_1$

$\Rightarrow a_1=\frac{169}{5}$

The sum of the first n-terms is given by the formula,

$S_n=\frac{n}{2}(2a_1+(n-1)d)$

To find $S_{31}$ , we substitute $n=31$ , $a_1=\frac{169}{5}$ and $d=-2.1$ .

$\Rightarrow S_{31}=\frac{31}{2}(2(\frac{169}{5}+(31-1)(-2.1))$

$\Rightarrow S_{31}=\frac{31}{2}(2(\frac{169}{5}+(30)(-2.1))$

$\Rightarrow S_{31}=\frac{31}{2}(\frac{23}{5})$

$\Rightarrow S_{31}=\frac{713}{10}$

$\Rightarrow S_{31}=71.3$

The correct answer is D

8 0

3 years ago

Read 2 more answers

Quadrilateral LMNO is similar to quadrilateral PQRS. Find the measure of side QR.

dalvyx [7]

Answer:

The measure of the side $QR$ is 8.8.

Step-by-step explanation:

Since $LMNO \sim PQRS$ , then $SP \propto OL$ , $RS \propto ON$ , $RQ \propto MN$ and $QP \propto LM$ . From figure we have the following relationship:

$k = \frac{OL}{SP} = \frac{ON}{RS} = \frac{MN}{QR} = \frac{ML}{QP}$ (1)

Where $k$ is the proportionality ratio.

If we know that $SP = 13, OL = 55, MN = 37$ , then the measure of side $QR$ is:

$k = \frac{OL}{SP}$ (1b)

$k = \frac{55}{13}$

$k = \frac{MN}{QR}$

$QR = \frac{MN}{k}$ (1c)

$QR = \frac{37}{\frac{55}{13} }$

$QR = 8.745$

The measure of the side $QR$ is 8.8.

4 0

3 years ago

Steps to solve: 28x - 12 + 2x - 4 - x

Musya8 [376]

Let's simplify by step

28x-12+2x-4-x

28x+-12+2x+-4+-x

Combine like terms

28x+-12+2x+-4+-x

(28x+2x+-x)+(-12+-4)

29x+-16

= 29x-16

I hope that's help !

8 0

3 years ago

Find the slope of the graph of y=−45x−2.

andriy [413]

Answer:

The slope in this equation is $45$ .

Step-by-step explanation:

Slope-intercept form: $y = mx + b$

m = slope

b = y-intercept

x = variable

$y = mx + b\\y = -45x -2$

7 0

3 years ago

B. Un autobús hace diariamente tres viajes de ida y

Lerok [7]

Answer:

BEANSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSS

Step-by-step explanation:

6 0

2 years ago