Step-by-step explanation:
this creates 2 similar triangles.
that means all angles are the same. and all the side lengths of one triangle correlate to the corresponding side lengths of the other triangle by the same multiplication factor.
her shadow is 23.05 - 18.9 = 4.15 m long.
the factor between the shadow lengths is then
4.15 × f = 23.05
f = 23.05 / 4.15 = 5.554216867...
the same factor now applies to the relation of the heights :
1.45 × 5.554216867... = 8.053614458... m
rounded the tree is 8.05 m tall.
Answer:
CI = 29.8 ± 3.53
Critical value is z = 2.58
Step-by-step explanation:
First of all let's find margin of error. It is given by the formula;
ME = zσ/√n
We are given;
Standard deviation; σ = 3.62
Sample size; n = 7
Mean; x¯ = 29.8
Now, z-value for 99% Confidence level is 2.58
Thus;
ME = (2.58 × 3.62)/√7
ME = 3.53
CI is written as;
CI = x¯ ± ME
CI = 29.8 ± 3.53
Critical value is z = 2.58
Answer:
for quadratic equation 1
y^2-10y+21=0
Step-by-step explanation:
y^2-7y-3y+21=0
y(y-7)-3(y-7)=0
(y-7)(y-3)=0
y-7=0,y-3=0
y=7,y=3
y=(3,7)
for quadratic equation 2
16p^2-8p+1=0
16p^2-4p-4p+1=0
4p(4p-1)-1(4p-1)=0
(4p-1)twice=0
4p-1=0,4p-1=0
4p=1
p=1/4 twice
for quadratic equation 3
x^2-400=0
x^2=400
x=√400
x=20
for quadratic equation 4
-16m^2-8m-1=0
multiply the equation by -
16m^2+8m+1=0
16m^2+4m+4m+1=0
4m(4m+1)1(4m+1)=0
4m+1=0 twice
m=-1/4 twice
for quadratic equation 5
-3n^2+75=0
divide both side by -3
-3n^2/-3=-75/-3
n^2=25
n=√25
n=5
Answer:
11
Step-by-step explanation:
Answer:
Step-by-step explanation:Given that the numerator of a given fraction is 4 less than its denominator.
Also given that 3 is subtracted from the numerator and 5 is added to the denominator, the fraction becomes one by fourth .
Let the fraction be
Since the numerator of a given fraction is 4 less than its denominator we have,
Numerator=Denominator-4
⇒ a=b-4
Since 3 is subtracted from the numerator and 5 is added to the denominator, the fraction becomes one by fourth we have
4(a-3)=1(b+5)
4a-12=b+5
4a-b=17
4(b-4)-b=17 ( ∵ a=b-4)
4b-16-b=17
3b=17+16
3b=33
⇒ b=11
Now put b=11 in a=b-4 we get
a=11-4
⇒ the fraction is a/b=7/11
