Equation of a parabola is written in the form of f(x)=ax²+bx+c.
The equation passes through points (4,0), (1.2,0) and (0,12), therefore;
replacing the points in the equation y = ax² +bx+c
we get 0 = a(4)²+b(4) +c for (4,0)
0 = a (1.2)²+ b(1.2) +c for (1.2,0)
12 = a(0)² +b(0) +c for (0,12)
simplifying the equations we get
16a + 4b + c = 0
1.44a +1.2b + c = 0
+c = 12
thus the first two equations will be
16a + 4b = -12
1.44 a + 1.2b = -12 solving simultaneously
the value of a = 5/2 and b =-13
Thus, the equation of the parabola will be given by;
y= 5/2x² - 13x + 12 or y = 2.5x² - 13x + 12
Answer:
2x +3y=1⇒equation 1
3x=2y+8
3x-2y=8⇒equation 2
by elimination method,
2x+3y=1 ×2
3x-2y=8 ×3
4x+6y=2
9x-6y=24
cut 6y and -6y
4x+6y=2
9x-6y=24
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13x+0=26
13x=26
x=26/13
x=2
substitute x=2 in equation 1
2(2)+3y=1
4+3y=1
3y=1-4
3y=-3
y=-3/3
y=-1
therefore, x=2 and y=-1
hope it helps u!
Answer:
<em>There are 72 crayons in the box</em>
Step-by-step explanation:
<u>Fractions</u>
To solve this problem we'll manage numbers as fractions to keep the precision up to the end of it.
Lynn has a box of crayons. It's given 4/9 of the crayons are blue. The remaining crayons are:
From that portion, 65% are red, or equivalently, 35% are yellow.
We write 35% as a fraction:
Thus, the portion of yellow crayons is:
This fraction of x crayons is equal to 14, thus:
x = 72
There are 72 crayons in the box
The answer would be: He spent 17 hours on the phone
Explanation: $826.20 - $725= $101.2 - $40= $61.12 / $3.60= 17hrs
