Answer:
solve for x in the second equation is correct
Step-by-step explanation:
Here is the complete question
Which first step for solving the given system using substitution results in an equation without fractions?
(2x+6y=7
(6x + 18y = 24.... 2
Solve for x in the first equation,
Solve for y in the first equation,
Solve for x in the second equation
The best equation to she will be equation 2 since all the coefficients are end numbers
Let us make x t subject f the formula from equation 2;
From 2: 6x+18y = 24
Subtract 18y from both sides
6x+18y-18y = 24-18y
6x = 24-18y
Divide through by 6
6x/6 = 24/6 - 18y/6
x = 4-3y.
You can see that the resulting expression of x is not a fraction. Hence solve for x in the second equation is correct
Answer:
x² + y² + 4x - 2y + 1 = 0
Step-by-step explanation:
The equation of a circle is given by the general equation;
(x-a)² + (y-b)² = r² ; where (a,b) is the center of the circle and r is the radius.
In this case; the center is (-2,1)
We can get radius using the formula for magnitude; √((x2-x1)² + (y2-y1)²)
Radius = √((-4- (-2))² + (1-1)²)
= 2
Therefore;
The equation of the circle will be;
(x+2)² + (y-1)² = 2²
(x+2)² + (y-1)² = 4
Expanding the equation;
x² + 4x + 4 + y² -2y + 1 = 4 subtracting 4 from both sides;
x² + 4x + y² - 2y + 4 + 1 -4 = 0
= x² + y² + 4x - 2y + 1 = 0
Answer:
y=7x-3
Step-by-step explanation:
Answer: B
Step-by-step explanation:
I used heron's formula.
6=.75x
x= 8 hours for the whole race
