5x=1/2y-1, find value of X; 1/4y=10x-1, find value of Y (use substitution)
I assume you mean:
5 x = (1/2) y - 1
(1/4) y = 10 x - 1
and we are to solve the two equations simultaneously using substitution and get for x first
so solve the first for x as a function of y
x = (1/10) y - 1/5
use that x in the second equation to get y
(1/4) y = 10 [ (1/10)y -1/5 ] - 1
y = 4 y - 8 - 4
3 y = 12
y = 4
Now use that value of y to get x
5 x = (1/2) 4 - 1
x = 1/5
i need help in finding this answer
find the value of r so that the line through (8,R) and (4,5) has a slope of negative
To find the value of x and y using substitution, we can solve one equation for either x or y and substitute it into the other equation.
1) 5x = (1/2)y - 1
Let's solve this equation for x:
Divide both sides of the equation by 5:
x = (1/10)y - 1/5
Now, we have the value of x in terms of y.
2) (1/4)y = 10x - 1
Since we have the expression for x from equation 1, let's substitute it into equation 2:
(1/4)y = 10((1/10)y - 1/5) - 1
Now, we simplify the equation:
(1/4)y = y - 2 - 1
(1/4)y = y - 3
To remove the fractions, we can multiply both sides of the equation by 4:
4 * (1/4)y = 4 * (y - 3)
y = 4y - 12
Now, let's solve for y:
Subtract 4y from both sides:
-3y = -12
Divide both sides by -3:
y = 4
Now, we have the value of y, which is 4. To find the value of x, substitute this value of y into equation 1:
x = (1/10)(4) - 1/5
x = 2/5 - 1/5
x = 1/5
Thus, the value of x is 1/5.