8x² - 4 = 28
8x² = 28 + 4
8x² = 32
x² = 32/8
x² = 4
x = <span>±2
</span>
Answer:
$420
Step-by-step explanation:
Calculate 3% of 3,500:
0.03*3500 = 105
105 per year for 4 years:
105*4 = 420
Answer
13
Step-by-step explanation:
We know that
sin²x+cos²x=1
so
clear cos x
cos x=(+/-)√[1-sin²x]
in this problem
<span>Angle 0 is in quadrant 1 -----> cos o and sin o are positive
</span>sin o=2/5
cos x=√[1-(2/5)²]----> cos o=√[1-4/25]----> cos o=√[21/25]---> cos o=√21/5
the answer is
cos o=√21/5
