The operation of addition is closed for the set of all integers. True or False?

Natasha2012 [34]

Convention in algebra is that we use letters such as a, b, c, etc., for parameters and letters such as x, y z, and so on, for variables.

Thus the parameters here are a, b and k. k is the constant of proportionality.

5 0

3 years ago

What is the correct first step to solve this system of equations by elimination?

storchak [24]

$\bold{\huge{\pink{\underline{ Solution }}}}$

$\bold{\underline{ Given }}$

We have given two linear equations that is 2x - 3y = -6 and x + 3y = 12 .

$\bold{\underline{ To \: Find }}$

We have to find the value of x and y by elimination method.

$\bold{\underline{ Let's \: Begin }}$

$\sf{ 2x - 3y = -6 ...eq(1)}$

$\sf{ x + 3y = 12 ...eq(2)}$

Multiply eq( 2 ) by 2 :-

$\sf{ 2( x + 3y = 12 )}$

$\sf{ 2x + 6y = 24 }$

Subtract eq(1) from eq(2) :-

$\sf{ 2x + 6y -( 2x - 3y) = 24 -(-6)}$

$\sf{ 2x + 6y - 2x + 3y = 24 + 6 }$

$\sf{ 9y = 30 }$

$\sf{ y = 30/9}$

$\sf{\red{ y = 10/3}}$

Now, Subsitute the value of y in eq( 1 ):-

$\sf{ 2x - 3(10/3) = -6 }$

$\sf{ 2x - 10 = -6 }$

$\sf{ 2x = -6 + 10}$

$\sf{ x = 4/2}$

$\sf{\red{ x = 2}}$

Hence, The value of x and y is 2 and 10/3

6 0

3 years ago

Kelso is in charge of a bake sale. On each table, t, there will be a platter of 24 cookies and 2 bowls of brownies with b browni

Phantasy [73]

24*7 = 168
(2*12)*7=168
168*2=336

336 Total sweets

8 0

3 years ago

What is the sum of the first five terms of a geometric series with A1 equals 20 and R equals 1/4

sweet-ann [11.9K]

Sum = 20(1-(1/4)^5) / (1-1/4) = 26.64

6 0

3 years ago

A small theater with 200 seats sells two kinds of tickets for a performance. Premium tickets sell for $20 each and Standard tick

KATRIN_1 [288]

P + s = 200......p = 200 - s
20p + 15s = 3400

20(200 - s) + 15s = 3400
4000 - 20s + 15s = 3400
-20s + 15s = 3400 - 4000
-5s = - 600
s = -600/-5
s = 120 <=== there were 120 standard tickets sold

p + s = 200
p + 120 = 200
p = 200 - 120
p = 80 <=== there were 80 premium tickets sold

7 0

4 years ago