Answer: Length: 24
Step-by-step explanation:
We will check if y and 60cm are parallel.
If the lengths 28cm, 56cm and 15cm, 30cm are in proportion, then y and the segment 60cm are parallel.
OK. We know: y and 60cm are parallel. Therefore we have equation:
<h3>Answer: y = 90 cm.</h3>
You subrtact.
112-98= 14
You earned $14 for profit.
Answer:
a. – 4 or –3
b. –4 or –2
c. 4 or –3
d. 7 or 4
Step-by-step explanation:
To factorize the above expression, multiply the first and last term together, then find two factors of the result such that their sum will result to the middle term of the expression.
Now, we shall give the answers to the question.
a. x² + 7x + 12 = 0
x² + 3x + 4x + 12 = 0
Factorise
x(x + 3) + 4(x + 3) = 0
(x + 4)(x + 3) = 0
x + 4 = 0 or x + 3 = 0
x = 0 – 4 or x = 0 – 3
x = – 4 or –3
Therefore, the roots of the equation are – 4 or –3
b. t² + 6t + 8 = 0
t² + 2t + 4t + 8 = 0
Factorise
t(t + 2) + 4(t + 2) = 0
(t + 4)(t + 2) = 0
t + 4 = 0 or t + 2 = 0
t = 0 – 4 or t = 0 – 2
t = –4 or –2
Therefore, the roots of the equation are –4 or –2
c. 2n² – 2n – 24 = 0
Divide through by 2
n² – n – 12 = 0
n² + 3n – 4n – 12 = 0
Factorise
n(n + 3) – 4(n + 3) = 0
(n – 4)(n + 3) = 0
n – 4 = 0 or n + 3 = 0
n = 0 + 4 or n = 0 – 3
n = 4 or n = –3
Therefore, the roots of the equation are 4 or –3
d. y² – 11y + 28 = 0
y² – 4y – 7y + 28 = 0
Factorise
y(y – 4) – 7(y – 4) = 0
(y – 7)(y – 4) = 0
y – 7 = 0 or y – 4 = 0
y = 0 + 7 or y = 0 + 4
y = 7 or 4
Therefore, the roots of the equation are 7 or 4.
