Budhas 7/10 of a cake left. Two of his friends are over for dessert. Estimate how much cake
each of them, including Bud, will get.

A.1/2 of the cake

B.1/4of the cake

C.3/4of the cake

D.1 1/4of the cake

B

Step-by-step explanation:

Two friends + Bud = 3 people

7/10 = 70%, or less than a full cake

D is more than a full cake so this cannot be the answer.

C is 3/4 which 75% for each person, but there is only 70% to begin with so this is impossible.

B is 1/4 for each person also known as 25% for each person. 25% × 3 people = 75% which is slightly over how much cake Bud has (70%).

A is 1/2 for each person, but there isn't enough cake to go around to give each person a half piece.

The soundest solution would be B. Since the problem calls for estimations, B gives about 25% to each person, totaling to 75% after 3 people. Although we only have 70%, we are only estimating. A 5% difference is a good estimate.

{x = -1/2 ,   y = -1

step-by-step explanation:

solve the following system:

{2 x + y = -2

{10 x - 3 y = -2

in the first equation, look to solve for y:

{2 x + y = -2

{10 x - 3 y = -2

subtract 2 x from both sides:

{y = -2 x - 2

{10 x - 3 y = -2

substitute y = -2 x - 2 into the second equation:

{y = -2 x - 2

{10 x - 3 (-2 x - 2) = -2

10 x - 3 (-2 x - 2) = (6 x + 6) + 10 x = 16 x + 6:

{y = -2 x - 2

{16 x + 6 = -2

in the second equation, look to solve for x:

{y = -2 x - 2

{16 x + 6 = -2

subtract 6 from both sides:

{y = -2 x - 2

{16 x = -8

divide both sides by 16:

{y = -2 x - 2

{x = -1/2

substitute x = -1/2 into the first equation:

{y = -1

{x = -1/2

collect results in alphabetical order:

answer:   {x = -1/2 ,   y = -1

5x + 3y = - 4

step-by-step explanation:

the equation of a line in standard form is

ax + by = c ( a is a positive integer and b, c are integers )

express the line first of all in slope- intercept form

y = mx + c ( m is the slope and c the y-intercept )

to calculate m use the gradient formula

m = ( y₂ - y₁ ) / ( x₂ - x₁ )

with (x₁, y₁ ) = (7, - 3) and (x₂, y₂ ) = (4, - 8)

m = = -

y = - x + c ← is the partial equation

to find c substitute either of the 2 points into the partial equation

using (4, - 8 ), then

- 8 = - + c ⇒ c = -

y = - x - ← in slope-intercept form

multiply all terms by 3 to eliminate the fractions

3y = - 5x - 4 ( add 5x to both sides )

5x + 3y = - 4 ← in standard form