Step-by-step explanation:
(a-b)^2=(a^2-2*a*b+b^2)
4*(x^2-2x+1)-9=4x^2-8x+4-9=4x^2-8x-5
if you have to calculate the Δ
there is it: 4x^2-8x-5=0
Δ=b^2-4*a*c=64-4*4*(-5)=64+80=144
-b±Δ/2*a=8±12/8=
=8+12/8=20/8|:4=5/2
=8-12/8=-4/8|:4=-1/2
Answer:
19%
Step-by-step explanation:
Last year:
Number of boys on honor roll = 96
Number of girls on honor roll = 60
Total students on honor roll = Number of boys on honor roll + Number of girls on honor roll
= 96 + 60
= 156
This year:
The number of boys on the honor roll increased by 25%
Number of boys on honor roll = 25% of 96 + 96
= 0.25×96 + 96
= 24 + 96
= 120
The number of girls on the honor roll increased by 10%.
Number of girls on honor roll = 10% of 60 + 60
= 0.10 × 60 + 60
= 6 + 60
= 66
Total students on honor roll = Number of boys on honor roll + Number of girls on honor roll
= 120 + 66
= 186
Percentage the total number of students on the honor roll increase = (186 - 156) / 156 × 100
= 30 / 156 × 100
= 0.19 × 100
= 19% to the nearest tenth
Answer:
8: yes
14: no
6: yes
9: yes
Step-by-step explanation:
Hope this helps!
(P.S.I changed the answer)
