If x + 4y = 6 and you subst. -x+3 for y, you get x + 4(-x+3) = 6.
Then x - 4x + 12 = 6, or -3x = -6, or x = 2. Since y = -x+3, here y = -(2)+3 = 1.
Thus, the solution to this system of linear equations is (2,1).
Answer:
x = 21
Step-by-step explanation:
The sum the the interior angles of a triangle is 180°.
We know that the three angles of the triangle is 100°, x° - 4, and 3x°.
The sum of 100°, x° - 4, and 3x° must equal 180°. We can turn this into the equation:
100 + x - 4 + 3x = 180
(I got rid of the degree signs because they are not necessary when finding x.)
Now, to find the value of x, we would have to solve for x in the equation 100 + x - 4 + 3x = 180.
100 + x - 4 + 3x = 180
Subtract 100 from both sides to get rid of the 100 on the left side.
x - 4 + 3x = 180 - 100
Simplify.
x - 4 + 3x = 80
Add 4 from both sides to get rid of the -4 on the left side.
x + 3x = 80 + 4
Simplify and combine like terms.
4x = 84
Divide 4 from both sides to get rid of the coefficient of 4 on the left side.
x = 84/4
Simply.
x = 21
The value of x would be 21.
x = 21
I hope you find this helpful. :)
Answer:
gf(5) = 289.
fg(x) = 3x^2 + 2.
Step-by-step explanation:
f(5) = 3(5) + 2 = 17
So gf(5) = 17^2 = 289.
fg(x) = 3(x^2) + 2 (we replace the x in f(x) by g(x)).
= 3x^2 + 2.
