Answer:
The values are
x = -25/9 = -2 7/9
y = 7/3 = 2 1/3
Step-by-step explanation:
3x + 2y = -13 --------eqn 1
3x + 4y = 1-------------eqn2
Using eqn 2 to get the value of y
3x + 4y = 1
4y = 1 - 3x
Dividing both sides by 4,to get y
4y/4 =( 1 -3x) / 4
y = (1 - 3x) / 4
Since we've gotten the value for y, substitute the value into eqn 1
3x + 2y = -13
3x + 2(3x - 1)/4 = -13
Opening the bracket
3x + (6x - 2)/4 = -13
LCM = 4
(12x + 6x - 2) / 4 = -13
18x - 2 / 4 = -13
Then we cross multiply
18x - 2 = -13 * 4
18x - 2 = - 52
18x = -52 + 2
18x = -50
Divide both sides by 18, to get the value of x
18x/18 = -50/18
x = -25/9
or x = -2 7/9
The value of x is now known, so let's go back to eqn 2
Substitute x = - 25/9
3x + 4y = 1
3(-25/9) + 4y = 1
Open the bracket
-75/9 + 4y = 1
Make y the subject of the formula
4y = 1 + 75/9
LCM = 9
4y = (9 + 75)/ 9
4y = 84/9
To get y, divide both sides by 4
4y/4 = 84/9 / 4/1
y =
Note : when division changes to multiplication, it always be in its reciprocal form
y = 84/9 / 1/4
y = 84 * 1 / 9 *4
y = 84/ 36
y = 7/3
Or
y = 2 1/3
Answer:
a = 12
Step-by-step explanation:
add 2 to each side
5a/3 = a/4 + 17
distribute 12 to remove fractions
20a = 3a + 204
17a = 204
a = 12
40 over 100 and 55 over n cross multiply 55 x 100 and divide by 40.which gives you 137.5
15 since its in the middle of 10 and 20
3 to the power of 9 over 10
