1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
MissTica
3 years ago
11

Find the value of m .​

Mathematics
1 answer:
kondor19780726 [428]3 years ago
7 0

Step-by-step explanation:

if the 2 matrices are inverse, then their product must be the identity matrix

1 0

0 1

so,

m×3 + 2×-7 = 1

7×3 + 3×-7 = 0

m×-2 + 2×m = 0

7×-2 + 3×m = 1

that means we have to solve only

3m - 14 = 1

3m = 15

m = 5

You might be interested in
PLEASE PEOPLE, HELP ME!! Geometry
Oksanka [162]
I use the sin rule to find the area

A=(1/2)a*b*sin(∡ab)

1) A=(1/2)*(AB)*(BC)*sin(∡B)
sin(∡B)=[2*A]/[(AB)*(BC)]

we know that
A=5√3
BC=4
AB=5
then

sin(∡B)=[2*5√3]/[(5)*(4)]=10√3/20=√3/2
(∡B)=arc sin (√3/2)= 60°

 now i use the the Law of Cosines 

c2 = a2 + b2 − 2ab cos(C)

AC²=AB²+BC²-2AB*BC*cos (∡B)

AC²=5²+4²-2*(5)*(4)*cos (60)----------- > 25+16-40*(1/2)=21

AC=√21= 4.58 cms

the answer part 1) is 4.58 cms

2) we know that

a/sinA=b/sin B=c/sinC

and

∡K=α

∡M=β

ME=b

then

b/sin(α)=KE/sin(β)=KM/sin(180-(α+β))

KE=b*sin(β)/sin(α)

A=(1/2)*(ME)*(KE)*sin(180-(α+β))

sin(180-(α+β))=sin(α+β)

A=(1/2)*(b)*(b*sin(β)/sin(α))*sin(α+β)=[(1/2)*b²*sin(β)/sin(α)]*sin(α+β)

A=[(1/2)*b²*sin(β)/sin(α)]*sin(α+β)

KE/sin(β)=KM/sin(180-(α+β))

KM=(KE/sin(β))*sin(180-(α+β))--------- > KM=(KE/sin(β))*sin(α+β)

the answers part 2) are

side KE=b*sin(β)/sin(α)
side KM=(KE/sin(β))*sin(α+β)
Area A=[(1/2)*b²*sin(β)/sin(α)]*sin(α+β)

5 0
3 years ago
Write an equation to represent the following situation. Justin wants to earn 500 minutes on Khan Academy He currently has 120 mi
Alisiya [41]

Answer:

500=120+60

Variable would either be M or D For 60

Step-by-step explanation:


5 0
3 years ago
Make an approximate conversion from English to metric. <br><br> 9 ft to meters
Anna71 [15]

Answer:

2.7 meters

Step-by-step explanation:

I hope this helped

4 0
3 years ago
What is the value of -9 + (-4 + 7) (2)?
RUDIKE [14]

Answer:

try -3

Step-by-step explanation:

5 0
3 years ago
Read 2 more answers
(x^4)^2 <br> how do I simplify this expression?
castortr0y [4]

Answer:

x^8

Step-by-step explanation:

(x^4)^2

~Apply power rule [ (a^b)^c = a^bc ]

x^4(2)

~Simplify

x^8

Best of Luck!

6 0
3 years ago
Read 2 more answers
Other questions:
  • Find the measurement of angle g.
    10·1 answer
  • Factorise this equation
    11·1 answer
  • Solve the equation. 31-12n=211​
    8·1 answer
  • 8/x = 5/9 solve for x
    14·1 answer
  • If y= 3x + 6, what is the minimum value of (x^3)(y)?
    13·1 answer
  • Colette is on a canoe trip. Her team paddles the canoe at a constant rate of 3 km/h and they portage at a
    13·1 answer
  • What’s the area of segment (shaded region) PLEASE HELP FAST
    6·1 answer
  • Solve x+1&gt;3. Graph the solution.
    9·1 answer
  • Solve -5w = -80 for w.<br><br> w =
    12·2 answers
  • A quadrilateral can be constructed with four obtuse angles. <br> True<br> False
    5·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!