Answer:
x intercept at (7/3 , 0)
y intercept at (0,-3)
Step-by-step explanation:
9x-7y=21
we need to find x and y intercepts
To find x intercept , plug in 0 for y
9x - 7(0) = 21
9x = 21
divide by 9 on both sides
x= 21/ 9 = 7/3
so x intercept at (7/3 , 0)
To find y intercept , plug in 0 for x
9(0) - 7(y) = 21
-7y = 21
divide by -7 on both sides
y= -3
so y intercept at (0,-3)
Answer: x = 5
Step-by-step explanation:
1. Set the two given expressions equal to each other (because the problem says they are interchangeable)
-5x = -40+3x
2. Subtract 3x from -5x to have x on one side of the equation.
-8x = -40
3. Divide each side by -8 to get the value of x.
x = 5
Answer:
x = -2 0r x = 6
Step-by-step explanation:
from the question
X² – 4x – 12=0
solve by completing the square method
we have;
X² – 4x – 12=0
X² – 4x = 12
to make the left hand side a perfect square we add 4 to both sides.
X² -4x + 4 = 12 + 4
X² -4x + 4 = 16
from left hand side X² -4x + 4
= (x -2) × ( x -2)
it can be simply expressed as
( x-2)²
so since X² -4x + 4 has been simplified to be ( x-2)²
then,
( x-2)² = 16
x - 2 = √ 16
since square root has two values it can either be positive or negative
so we have
x = 2 + √16
or
x = 2 - √16
therefore
x = 2 + √16
x = 2 + 4
x = 6
0r
x = 2 - 4
x = -2
