The sum of two numbers is 72 and their difference is 40. Using elimination method

Mathematics

1 answer:

d1i1m1o1n [39]3 years ago

3 0

Answer:

here's what we know:

a + b = 72

a - b = 26

We can use the elimination method to solve this problem:

a + b = 72

a - b = 26

---------------

2a = 98

Divide both sides by 2:

a = 49

So we now have:

49 + b = 72

and:

49 - b = 26

Subtract 49 from both sides:

b = 23

and

-b = -23 (multiply both sides by -1) → b = 23

Step-by-step explanation:

You might be interested in

irakobra [83]

Answer:

a) P(0, 2), Q(4, 0)

b) Please find attached the plot of the points P and Q on a chart made with MS Excel

c) Please find the graph of the line that represent the function 4·x + 2·y = 8 for values of x from -2 to 3 made with the Insert Chart feature on MS Excel

Step-by-step explanation:

The given equation for the line is 4·x + 2·y = 8

a) The coordinates of P = P(0, _)

Therefore, the point 'P', which is the point where the variable y = 0, is the point the (straight line) graph intercepts the x-axis (the x-intercept)

When y = 0 from the given equation, we get;

4·x + 2·y = 8

At the point y = 0;

4·x + 2 × 0 = 8

x = 8/4 = 2

x = 2

∴ The coordinates of P = P(0, _) = P(0, 2)

Similarly, when x = 0, we get;

4·x + 2·y = 8

At the point x = 0;

4 × 0 + 2·y = 8

y = 8/2 = 4

y = 4

∴ The coordinates of Q = Q(_, 0) = Q(4, 0)

b) Rewriting the given equation in terms of 'y' gives;

y = (8 - 4·x)/2 = 4 - 2·x

y = 4 - 2·x

With the help of MS Excel, the points P and Q are plotted in the attached graph

c) The line of the graph of the function 4·x + 2·y = 8 for values of x from -2 to 3 can be added by Changing the Chart Type to 'Scatter with Smooth Lines and Markers' within MS Excel as presented in the included graph of the line.