If you do 27-12 (which is 15) you add 15 to 13 and 20
Answer:
5 - 3i.
Step-by-step explanation:
2 + 4i + 3 - 7i Bring like terms together:
= 2 + 3 + 4i - 71
= 5 - 3i.
Answer: a) BC = 1386.8 ft
b) CD = 565.8 ft
Step-by-step explanation:
Looking at the triangle,
AD = BD + 7600
BD = AD - 7600
Considering triangle BCD, we would apply the the tangent trigonometric ratio.
Tan θ = opposite side/adjacent side. Therefore,
Tan 24 = CD/BD = CD/(AD - 700)
0.445 = CD/(AD - 700)
CD = 0.445(AD - 700)
CD = 0.445AD - 311.5 - - - - - - - -1
Considering triangle ADC,
Tan 16 = CD/AD
CD = ADtan16 = 0.287AD
Substituting CD = 0.287AD into equation 1, it becomes
CD = 0.445AD - 311.5
0.287AD = 0.445AD - 311.5
0.445AD - 0.287AD = 311.5
0.158AD = 311.5
AD = 311.5/0.158
AD = 1971.52
CD = 0.287AD = 0.287 × 1971.52
CD = 565.8 ft
To determine BC, we would apply the Sine trigonometric ratio which is expressed as
Sin θ = opposite side/hypotenuse
Sin 24 = CD/BC
BC = CD/Sin24 = 565.8/0.408
BC = 1386.8 ft
X3-7x=6x-12
x3-7x-6x+12=0
x3-13x+12=0
(x-1)(x2+x-12)=0
Calculate delta of the second bracket:
delta = 1+4*12=49
sqrt(delta)=sqrt(49)=7
x_1=(-1-7)/2=-4
x_2=(-1+7)/2=3
(x-1)(x+4)(x-3)=0
Answear:
Roots: x=1, x=-4, x=3.
It is 42. It is easy like the bottom one
