Answer:
They walked about 125.6 meters
Step-by-step explanation:
40 is the diameter and just multiply it by 3.14
Answer:
t=1/6 or 0.166
Step-by-step explanation:
add like terms: 12t=2
divide by 12: t=1/6
simply to decimal: 0.166
Answer:
x = 8.64
x = - 7.64
Both to 2 d.p
Step-by-step explanation:
Firstly, - 8 both side - cancels the +8 & get the surd to equal x - 8
Then, square root both side, to get:
x-2= x^2 - 64
+ 2 both side
x = x^2 - 66
-x
0= x^2 - 66 - x
x^2 - x - 66 = 0
general equation for quadratic is ax^2 + bx + c
Now, we can find the value of a, b, c using x^2 - x - 66 = 0
a=1
b= - 1
c= - 66
Now use quadratic formula
x = -b±√(b²-4ac))/(2a
= --1 + √ - 1 x - 1 - 4x1x-66 / 2x1
= 8.639.....
Now repeat with - b - & not - b +
x = -b±√(b²-4ac))/(2a
= --1 - √ - 1 x - 1 - 4x1x-66 / 2x1
= - 7.639.......
hmmmm
b = brother
s = sister
a = my age
so your brother is 5 years older, b = a + 5.
and your sister is 3 years younger, s = a - 3.
that means your sister is
![\bf \begin{cases} b=a+5\implies b-5=\boxed{a}\\ s=a-3\\[-0.5em] \hrulefill\\ s=\boxed{b-5}-3\implies s=b-8 \end{cases} \\\\\\ \stackrel{\textit{if your sister is "m" years old, say s = m}}{m=b-8}\implies \blacktriangleright m+8=b \blacktriangleleft](https://tex.z-dn.net/?f=%5Cbf%20%5Cbegin%7Bcases%7D%20b%3Da%2B5%5Cimplies%20b-5%3D%5Cboxed%7Ba%7D%5C%5C%20s%3Da-3%5C%5C%5B-0.5em%5D%20%5Chrulefill%5C%5C%20s%3D%5Cboxed%7Bb-5%7D-3%5Cimplies%20s%3Db-8%20%5Cend%7Bcases%7D%20%5C%5C%5C%5C%5C%5C%20%5Cstackrel%7B%5Ctextit%7Bif%20your%20sister%20is%20%22m%22%20years%20old%2C%20say%20s%20%3D%20m%7D%7D%7Bm%3Db-8%7D%5Cimplies%20%5Cblacktriangleright%20m%2B8%3Db%20%5Cblacktriangleleft)
Ok so remember
order of simplification
PEMDAS
parenthaseese
exponents
multiplicaton or division whichever comes first
addition or subtraction whichever comes first
ok so remmeber work from the left to right parenthasees first and work from inside to outer parenthasees
so first one
innermost parenthasees first so
first step is 2-4
subtract 4 from 2
second one
if xy=0 then assume x and y=0 so
(a+2)(b-9)=0
a+2=0
a=-2
b-9=0
b=9
so answe ris a=-2
b=9
third questions
innermost parenthaees first
subtract 4 from 2
ok
1. subtrac 4 from 2
2. a=-2, b=9
3. subtract 4 from 2
