Answer:
Step-by-step explanation:
6x + 3y = -18
Taking 3 common from left side
so, 3(2x+y) = -18
2x+y = -18/3
2x+y = -6 (equation 1)
and, 7x + 7y = 0
Taking 7 as commom from left side
7(x + y) = 0
x + y = 0/7
x + y = 0 (equation 2)
now , by using elimination method
subtracting equation2 from equation1
2x + y - (x + y)= -6 - 0
2x + y - x - y = -6
x = -6
so, x = -6
substituting value of x in equation 1
2(-6) + y = -6
-12 + y = -6
y = -6 +12
y = 6
hence, the value of x = -6
and value of y = 6
Answer:
The pencil cost $0.05 and the pen cost $1.05.
Step-by-step explanation:
Let, the price of the pencil is $ .
Given that the pen costs a dollar more than the pencil,
So, the price of the pen=$+1.
Therefore, ++1=1.10
, 2+1=1.10
, 2=1.10–1
, 2=0.10
, =0.10/2
, =0.05
The pencil cost $0.05 and the pen cost $1.05.
Answer: m = -4 / 2 = -2 / 1 = -2
Slope (m) = -2
Step-by-step explanation:
Answer:
2
Step-by-step explanation:
So I'm going to use vieta's formula.
Let u and v the zeros of the given quadratic in ax^2+bx+c form.
By vieta's formula:
1) u+v=-b/a
2) uv=c/a
We are also given not by the formula but by this problem:
3) u+v=uv
If we plug 1) and 2) into 3) we get:
-b/a=c/a
Multiply both sides by a:
-b=c
Here we have:
a=3
b=-(3k-2)
c=-(k-6)
So we are solving
-b=c for k:
3k-2=-(k-6)
Distribute:
3k-2=-k+6
Add k on both sides:
4k-2=6
Add 2 on both side:
4k=8
Divide both sides by 4:
k=2
Let's check:
:


I'm going to solve
for x using the quadratic formula:







Let's see if uv=u+v holds.

Keep in mind you are multiplying conjugates:



Let's see what u+v is now:


We have confirmed uv=u+v for k=2.
16*8=128
12*12=144
128
+ 144
$272
Lee sold 16 hats