So legnt=l
width=w
l=-7+3w
l=3w-7
area=66
area=legnth times width or
area=lw
subisutte
area=lw
l=3w-7
66=(3w-7)(w)
66=3w^2-7w
subtrac 66 from both sides
0=3w^2-7w-66
factor
HOW TO
multiply 3 and -66=-198
find what 2 numbers add up to -7 and multiply to get -198
the numbers area 11 and -18
so
3w^2-18w+11w-66=0
factor
(3w^2-18w)+(11w-66)=0
(3w)(w-6)+(11)(w-6)=0
factor using distributive (ab+ac=a(b+c))
(3w+11)(w-6)=0
set them to zero
3w+11=0
subtract 11
3w=-11
legnths cannot be negative so we discard this
w-6=0
add 6
w=6
width=6
legnth=3w-7
length=3(6)-7
legnt=18-7
legnth=11
width=6
legnth=11
Answer:
x = 9
Step-by-step explanation:
Perimeter = 2 * width + 2 * length
= 2*11 + 2(x + 5) = 50
2x + 10 + 22 = 50
2x = 50 - 10 - 22
2x = 18
x = 9
Answer: i think it is... x = -19
Answer:
The probability that Jones is lying is 6/7
Step-by-step explanation:
First we will list out 2 different cases when the outcome is a lie
1.probability that Jones tells lies is = 0.6 and probability that dalgiliesh analyses it correctly is 0.8
So the probability that dagliesh correctly analyses that he is telling lies is 0.8*0.6=0.48
2.Probability that Jones tells truth is 0.4 and if dagliesh analyses it incorrectly (which has a probability of 0.2) the outcome(as analysed by dagiliesh) is a lie
So probability that dagliesh analyses Jones truth as a lie is 0.2*.0.4=0.08
Total probability of outcome being a lie is 0.48+0.08=0.56
But we need the probability of Jones actually saying a lie which is nothing but 0.48/0.56= 6/7
Step-by-step explanation:
- 2x-2y=-6
3x+4y=8
multiply equation (1) by 3 and equation (2) by 2
- 6x-6y=18
6x+8y=16
Add
2y=34
y= 34÷2
y=17
substitute 17 for y in equation (2)
3x+4y=8
3x+4(17)=8
3x+68=8
3x=8-68
3x=-60
x=-60÷3
x=-20
x=-20,y=17
