Answer:
x = 4
Step-by-step explanation:
5x-50=30-15x
5x +15x =30+50
20x= 80
Divide both sides of the equation by 20
x = 4
I hope it helps
Answer:
Only d) is false.
Step-by-step explanation:
Let
be the characteristic polynomial of B.
a) We use the rank-nullity theorem. First, note that 0 is an eigenvalue of algebraic multiplicity 1. The null space of B is equal to the eigenspace generated by 0. The dimension of this space is the geometric multiplicity of 0, which can't exceed the algebraic multiplicity. Then Nul(B)≤1. It can't happen that Nul(B)=0, because eigenspaces have positive dimension, therfore Nul(B)=1 and by the rank-nullity theorem, rank(B)=7-nul(B)=6 (B has size 7, see part e)
b) Remember that
. 0 is a root of p, so we have that
.
c) The matrix T must be a nxn matrix so that the product BTB is well defined. Therefore det(T) is defined and by part c) we have that det(BTB)=det(B)det(T)det(B)=0.
d) det(B)=0 by part c) so B is not invertible.
e) The degree of the characteristic polynomial p is equal to the size of the matrix B. Summing the multiplicities of each root, p has degree 7, therefore the size of B is n=7.
Answer:
5.85 m
Step-by-step explanation:
The width of the sand road can be calculated knowing its area and the dimensions of the rectangular garden as follows:

<u>Where:</u>
Ag: is the area of the rectangular garden
a: is the length of the rectangular garden = 50 cm = 0.5 m
b: is the width of the rectangular garden = 34 m
<u>Where</u>:
As: is the area of the sand road
The relation between the area of the sand road and the area of the rectangular garden is the following:



By solving the above equation for x we have two solutions:
x₁ = -23.10 m
x₂ = 5.85 m
Taking the positive value, we have that the width of the sand road is 5.85 m.
I hope it helps you!