Answer:
(7,2)
Step-by-step explanation:
x + y = 9 + 2x - 3y = 8 is really two equations, and you should show this by separating x + y = 9 from 2x - 3y = 8 through the use of a comma, or the word "and," or through writing only one equation per line.
Here you have the system of linear equations
x + y = 9
2x - 3y = 8.
Let's solve this system by elimination. Mult. the 1st eqn by 3, obtaining the system
3x + 3y = 27
2x - 3y = 8
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5x = 35, so that x = 7. Subbing 7 for x in x + y = 9, we get 7 + y = 9, indicating that y = 2.
Thus, the solution to this system of equations is (7,2).
The slope-intercept form is:
y = mx + b
where m = slope, and b = y-intercept.
You need a slope of 1, so m = 1.
You need a y-intercept of -1, so b = -1.
Replace m with 1 and b with -1 in the slope intercept form to get
y = 1x + (-1)
which simplifies to
y = x - 1
Answer:
f(x) = x(x-1)
Step-by-step explanation:
The easy way to do this is to look at it graphically. an inverse function is reflected across the line y=x. f(x)=x(x-1) is an upward opening parabola when reflected, there are two y-values for all positive values of x. A function can only have one y for every x.
Answer:
-4/5
Step-by-step explanation:
r=x/2
a=2x
ar²=-1/16
x^3=-1/8
x=-1/2
sn=a/1-r
=-4/5
1) The triangles are similar, so correponding sides have the same ratio.
.. 3x/20 = (4x +2)/28
.. 3x/5 = (4x +2)/7 . . . . . . . multiply by 4
.. 7*3x = 5(4x +2) . . . . . . . multiply by 35 = 5*7
.. 21x = 20x +10 . . . . . . . . eliminate parentheses
.. x = 10 . . . . . . . . . . . . . . . subtract 20x
2) The triangles are similar, so corresponding measures have the same ratio.
.. x/42 = 10/15
.. x = 42*(10/15) = 28
3) The third angle of triangle ABC is 180° -20° -80° = 80°. Then two of the angles of ABC match those of JKL. The 3rd answer selection is appropriate.