Answer:
x₁ = -4
x₂ = 3
Step-by-step explanation:
x²+ x + 12 = 0
x = {-1±√((1²)-(4*1*-12))} / (2*1)
x = {-1±√(1+48)} / 2
x = {-1±√49} / 2
x = {-1±7} / 2
x₁ = {-1-7} / 2 = -8/2 = -4
x₂ = {-1+7} / 2 = 6/2 = 3
Check:
x₁
-4² + (-4) - 12 = 0
16 - 4 - 12 = 0
x₂
3² + 3 - 12 = 0
9 + 3 - 12 = 0
3.7cm on the map represents 1850km in reality
3.7cm : 1850km
1cm : 1850/3.7 km
1cm : 500km
Scale statement for map is : 1cm : 500km.
That is 1cm on map represents 500km.
1cm : 500km. Recall 1km = 1000m = 100 000cm
1cm : 500* 100000cm
1cm : 50 000 000cm
1: 50 000 000.
Scale factor is 50 000 000.
Four positions of such a sequence are given to be 3s, and we have 10 choices for the remaining eight positions. So the number of such sequences is
or 100 million.
