Answer:
x=7 and y= 1/3
Step-by-step explanation:
we have -5x - 15 = -30 <=> x + 3 = 10
x= 7
if x=7
so 2×7 - 6y = 12 <=> 14 - 12 = 6×y
2 = 6y
y= 2/6 = 1/3
Answer:
Since stress is greater than ultimate strength, the wire will break.
Step-by-step explanation:
The titanium wire is experimenting an axial load. Ultimate strength equals 
. The wire shall break if and only if stress is at least equal to ultimate strength. The equation for axial stress (
), measured in pascals, in the wire with circular cross-section is:
(1)
Where:
- Axial force, measured in newtons.
- Cross-section diameter, measured in meters.
Please notice that axial force is the weight of the man hanging from wire.
If we know that 
and 
, then the axial stress experimented by the titanium wire is:
Since stress is greater than ultimate strength, the wire will break.
Answer:
2.17ft/s
Step-by-step explanation:
Look at the sketch of ladder at the beginning and after 3 seconds it starts to fall,
Distance of ladder from the wall 3 seconds after ladder starts to fall = Initial distance+ Velocity× time
= 6 + 2×3
= 12ft
Use trignometry to find out the speed of the top of ladder
cosθ= 12/20
θ= 0.825 rad
tan θ= v/2
v= 2.17ft/s
Question: If the subspace of all solutions of
Ax = 0
has a basis consisting of vectors and if A is a matrix, what is the rank of A.
Note: The rank of A can only be determined if the dimension of the matrix A is given, and the number of vectors is known. Here in this question, neither the dimension, nor the number of vectors is given.
Assume: The number of vectors is 3, and the dimension is 5 × 8.
Answer:
The rank of the matrix A is 5.
Step-by-step explanation:
In the standard basis of the linear transformation:
f : R^8 → R^5, x↦Ax
the matrix A is a representation.
and the dimension of kernel of A, written as dim(kerA) is 3.
By the rank-nullity theorem, rank of matrix A is equal to the subtraction of the dimension of the kernel of A from the dimension of R^8.
That is:
rank(A) = dim(R^8) - dim(kerA)
= 8 - 3
= 5
