The Area is the width<span> times the </span>height<span>: A = w x h;
Then, 64 = w x h;
h = 4 + w;
64 = 4w + w^2;
w^2 + 4w - 64 = 0;
We solve this equation: w1 </span>≈ 6,24 > 0 (okay); w2 ≈ - 10,24 < 0 (not okay);
<span>Finally, h1 </span>≈ 10,24;<span>
</span>
Answer: First half was 24 minutes
Step-by-step explanation:
Let the time taken to finish the second half be y.
Since the student used 2/3 of the second half time to finish the first half, first half = 2/3 × y = 2y/3
The entire exam is an hour which equals 60 minutes
First half + Second half = 60minutes
Note that first half is denoted as 2y/3 and second half is denoted by y.
2y/3 + y = 60
5y/3 = 60
Cross multiply
5y = 60 × 3
5y = 180
y = 180/5
y = 36
Second half took 36 minutes
Since first half is 2y/3, it will be:
(2×36) / 3
= 72/3
= 24minutes
First half took 24 minutes.
4.68 tons since you would multiply 2.1+0.5=2.6×1.8=4.68 tons