Answer:
6
Step-by-step explanation:
1. re-write the given system:
cx+3y=c-3; => y= -cx/3 +(c-3)/3
12x+cy=c; => y= -12x/c+c/12
2. according the condition the rule for the parallel graphs is:
-c/3= -12/c
3. to calculate the unknown 'c':
c²=36; ⇔c=±6
Answer:
y = 4x + 8
Step-by-step explanation:
1) Find slope:
y2-y1/x2-x1
12-8/1-0 = 4/1 = 4
Slope = 4
2) Plug in a point in point-slope form
y-y1=m(x-x1)
y-8=4(x-0) =
y-8=4x-0 -> add 8 to both sides
y=4x+8
if it is solution point (4, –2) must satisfy both equations
(1) –3x – 2y = –8-->-3*4-2*(-2)=-8
-12+4=-8 then-->-8=-8 ok
(2) y = 2x – 5
-2=2*4-5=3---------->-2 is not 3
the point (4, –2) is not solution of the system of equations
Let Ted be x.
Ed is 7 years older = x + 7
Ed = (3/4)Ted
(x + 7) = (3/4)x
x + 7 = 3x/4
x - 3x/4 = -7
x/4 = -7
x = -28, Ted = -28 years.
(x + 7) = -28 + 7 = -21, Ed = -21 years
Goodness. We had negative numbers for the ages, well does that make sense? No it doesn't.
Our answer is correct. But the sense in the question is lacking. The question has been wrongly set.
<span>We might assume negative ages to mean before they came into the world, before birth! </span>
