Question

1
Here are two right-angled triangles.
6 cm
Circle the value of y.
11
10 cm
7.5
y cm
9
15 cm
Not drawn
accurately
X
4
[1 mark]

Answer 1

Answer:

y = 9

Step-by-step explanation:

The two triangles are similar, by the AA postulate.

Then the ratios of corresponding sides are in proportion , that is

$\frac{y}{6}$ = $\frac{15}{10}$ ( cross multiply )

10y = 6 × 15 = 90 ( divide both sides by 10 )

y = 9

Answer 2

Answer:

9cm

Step-by-step explanation:

To find out what y is, we have to use a method called " cross multiply ".

Cross multiply fractions by multiplying the denominator of one fraction with the numerator of the other fraction and then comparing the two values

We can set up an equation and do just that.

$\frac{6}{10} = \frac{y}{15}$

When you cross multiply 6 and 15, you get 90.

When you cross multiply 10 and y ,  you get 10y.

In order to solve for y, we get make this an algebraic equation.

10y = 90

Divide each side by 10 to get the value of x.

y = 9

The value of y is 9 cm.