Find the sum of the first 20terms of this arithmetic progression: 2,5,8,11,.......

1 answer:

8 0

Y = -1 + 3x... y1= 2, y2=5... so the 20th term will be 59. There will be ten pairs (i.e 2,59 equal 61... 5,56 equal 61) so multiply this 61 by 10 and your sum will be 610

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Find the solution of the system of equations.<br><br> x-y=-3<br>-8x+y=45

mezya [45]

Answer:

x = 17, y = 28

Step-by-step explanation:

1. Isolate for x in "x - y = -3, -8":

x - y+y = -3, -8+y

x = -11 + y

2. Substitute "x = -11 + y" in for x in the second expression:

-11 + y + y = 45

3. Simplify:

-11 + 2y = 45

4. Isolate y:

-11+11 +2y = 45+11

2y = 56

$\frac{2y}{2} = \frac{56}{2}$

y = 28

5. Substitute the new y-value into the first equation:

x = -11 + 28

x = 17

hope this helps!

5 0

1 year ago

What is the area of this composite figure?

Mkey [24]

We have two congruent trapezoids.

The formula of an area of a trapezoid:

$A=\dfrac{base_1+base_2}{2}\cdot\ height$

We have:

$base_1=210\ mm\\\\base_2=150\ mm\\\\height=55\ mm$

Substitute:

$A=\dfrac{210+150}{2}\cdot55=\dfrac{360}{2}\cdot55=180\cdot55=9,900\ mm^2$

Answer:

$2A=2\cdot9,900\ mm^2=19,800\ mm^2$

6 0

3 years ago

-1/5y+7=7<br> What is the value of y?

liq [111]

The answer is y=0

See the attached photo for details

Hope this helps! Please make me the brainliest, it’s not necessary but appreciated, I put a lot of effort and research into my answers. Have a good day, stay safe and stay healthy.